Groups: refactored to use group ID, not group name, plus fixes, etc.

src/main/java/org/qora/api/model/GroupWithMemberInfo.java

@@ -25,14 +25,30 @@ public class GroupWithMemberInfo {
 	@XmlElement(name = "admins")
 	public List<String> groupAdminAddresses;
 
+	@XmlAccessorType(XmlAccessType.FIELD)
+	@Schema(description = "Member info")
+	public static class MemberInfo {
+		public String member;
+		public long joined;
+
+		// For JAX-RS
+		protected MemberInfo() {
+		}
+
+		public MemberInfo(GroupMemberData groupMemberData) {
+			this.member = groupMemberData.getMember();
+			this.joined = groupMemberData.getJoined();
+		}
+	}
+
 	@XmlElement(name = "members")
-	public List<GroupMemberData> groupMembers;
+	public List<MemberInfo> groupMembers;
 
 	// For JAX-RS
 	protected GroupWithMemberInfo() {
 	}
 
-	public GroupWithMemberInfo(GroupData groupData, List<String> groupAdminAddresses, List<GroupMemberData> groupMembers, Integer memberCount) {
+	public GroupWithMemberInfo(GroupData groupData, List<String> groupAdminAddresses, List<MemberInfo> groupMembers, Integer memberCount) {
 		this.groupData = groupData;
 		this.groupAdminAddresses = groupAdminAddresses;
 		this.groupMembers = groupMembers;

src/main/java/org/qora/api/resource/GroupsResource.java

@@ -26,6 +26,7 @@ import org.qora.api.ApiError;
 import org.qora.api.ApiErrors;
 import org.qora.api.ApiExceptionFactory;
 import org.qora.api.model.GroupWithMemberInfo;
+import org.qora.api.model.GroupWithMemberInfo.MemberInfo;
 import org.qora.crypto.Crypto;
 import org.qora.data.group.GroupAdminData;
 import org.qora.data.group.GroupBanData;
@@ -39,7 +40,7 @@ import org.qora.data.transaction.CreateGroupTransactionData;
 import org.qora.data.transaction.GroupBanTransactionData;
 import org.qora.data.transaction.GroupInviteTransactionData;
 import org.qora.data.transaction.GroupKickTransactionData;
-import org.qora.data.transaction.GroupUnbanTransactionData;
+import org.qora.data.transaction.CancelGroupBanTransactionData;
 import org.qora.data.transaction.JoinGroupTransactionData;
 import org.qora.data.transaction.LeaveGroupTransactionData;
 import org.qora.data.transaction.RemoveGroupAdminTransactionData;
@@ -56,7 +57,7 @@ import org.qora.transform.transaction.CreateGroupTransactionTransformer;
 import org.qora.transform.transaction.GroupBanTransactionTransformer;
 import org.qora.transform.transaction.GroupInviteTransactionTransformer;
 import org.qora.transform.transaction.GroupKickTransactionTransformer;
-import org.qora.transform.transaction.GroupUnbanTransactionTransformer;
+import org.qora.transform.transaction.CancelGroupBanTransactionTransformer;
 import org.qora.transform.transaction.JoinGroupTransactionTransformer;
 import org.qora.transform.transaction.LeaveGroupTransactionTransformer;
 import org.qora.transform.transaction.RemoveGroupAdminTransactionTransformer;
@@ -101,7 +102,7 @@ public class GroupsResource {
 	}
 
 	@GET
-	@Path("/address/{address}")
+	@Path("/owner/{address}")
 	@Operation(
 		summary = "List all groups owned by address",
 		responses = {
@@ -115,12 +116,40 @@ public class GroupsResource {
 		}
 	)
 	@ApiErrors({ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
-	public List<GroupData> getGroupsByAddress(@PathParam("address") String address) {
+	public List<GroupData> getGroupsByOwner(@PathParam("address") String owner) {
-		if (!Crypto.isValidAddress(address))
+		if (!Crypto.isValidAddress(owner))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			List<GroupData> groups = repository.getGroupRepository().getGroupsByOwner(address);
+			List<GroupData> groups = repository.getGroupRepository().getGroupsByOwner(owner);
+
+			return groups;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
+	@GET
+	@Path("/member/{address}")
+	@Operation(
+		summary = "List all groups where address is a member",
+		responses = {
+			@ApiResponse(
+				description = "group info",
+				content = @Content(
+					mediaType = MediaType.APPLICATION_JSON,
+					array = @ArraySchema(schema = @Schema(implementation = GroupData.class))
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
+	public List<GroupData> getGroupsWithMember(@PathParam("address") String member) {
+		if (!Crypto.isValidAddress(member))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			List<GroupData> groups = repository.getGroupRepository().getGroupsWithMember(member);
 
 			return groups;
 		} catch (DataException e) {
@@ -149,28 +178,28 @@ public class GroupsResource {
 			if (groupData == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.GROUP_UNKNOWN);
 
-			List<GroupMemberData> groupMembers = null;
+			List<MemberInfo> members = null;
 			Integer memberCount = null;
 
 			if (includeMembers) {
-				groupMembers = repository.getGroupRepository().getGroupMembers(groupData.getGroupName());
+				List<GroupMemberData> groupMembers = repository.getGroupRepository().getGroupMembers(groupData.getGroupId());
 
-				// Strip groupName from member info
+				// Convert to MemberInfo
-				groupMembers = groupMembers.stream().map(groupMemberData -> new GroupMemberData(null, groupMemberData.getMember(), groupMemberData.getJoined(), null)).collect(Collectors.toList());
+				members = groupMembers.stream().map(groupMemberData -> new MemberInfo(groupMemberData)).collect(Collectors.toList());
 
-				memberCount = groupMembers.size();
+				memberCount = members.size();
 			} else {
 				// Just count members instead
-				memberCount = repository.getGroupRepository().countGroupMembers(groupData.getGroupName());
+				memberCount = repository.getGroupRepository().countGroupMembers(groupData.getGroupId());
 			}
 
 			// Always include admins
-			List<GroupAdminData> groupAdmins = repository.getGroupRepository().getGroupAdmins(groupData.getGroupName());
+			List<GroupAdminData> groupAdmins = repository.getGroupRepository().getGroupAdmins(groupData.getGroupId());
 
 			// We only need admin addresses
-			List<String> groupAdminAddresses = groupAdmins.stream().map(groupAdminData -> groupAdminData.getAdmin()).collect(Collectors.toList());
+			List<String> adminAddresses = groupAdmins.stream().map(groupAdminData -> groupAdminData.getAdmin()).collect(Collectors.toList());
 
-			return new GroupWithMemberInfo(groupData, groupAdminAddresses, groupMembers, memberCount);
+			return new GroupWithMemberInfo(groupData, adminAddresses, members, memberCount);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}
@@ -393,21 +422,21 @@ public class GroupsResource {
 	}
 
 	@POST
-	@Path("/unban")
+	@Path("/ban/cancel")
 	@Operation(
-		summary = "Build raw, unsigned, GROUP_UNBAN transaction",
+		summary = "Build raw, unsigned, CANCEL_GROUP_BAN transaction",
 		requestBody = @RequestBody(
 			required = true,
 			content = @Content(
 				mediaType = MediaType.APPLICATION_JSON,
 				schema = @Schema(
-					implementation = GroupUnbanTransactionData.class
+					implementation = CancelGroupBanTransactionData.class
 				)
 			)
 		),
 		responses = {
 			@ApiResponse(
-				description = "raw, unsigned, GROUP_UNBAN transaction encoded in Base58",
+				description = "raw, unsigned, CANCEL_GROUP_BAN transaction encoded in Base58",
 				content = @Content(
 					mediaType = MediaType.TEXT_PLAIN,
 					schema = @Schema(
@@ -418,7 +447,7 @@ public class GroupsResource {
 		}
 	)
 	@ApiErrors({ApiError.TRANSACTION_INVALID, ApiError.TRANSFORMATION_ERROR, ApiError.REPOSITORY_ISSUE})
-	public String groupBan(GroupUnbanTransactionData transactionData) {
+	public String cancelGroupBan(CancelGroupBanTransactionData transactionData) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			Transaction transaction = Transaction.fromData(repository, transactionData);
 
@@ -426,7 +455,7 @@ public class GroupsResource {
 			if (result != ValidationResult.OK)
 				throw TransactionsResource.createTransactionInvalidException(request, result);
 
-			byte[] bytes = GroupUnbanTransactionTransformer.toBytes(transactionData);
+			byte[] bytes = CancelGroupBanTransactionTransformer.toBytes(transactionData);
 			return Base58.encode(bytes);
 		} catch (TransformationException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.TRANSFORMATION_ERROR, e);
@@ -651,7 +680,7 @@ public class GroupsResource {
 	}
 
 	@GET
-	@Path("/invites/{groupname}")
+	@Path("/invites/{groupid}")
 	@Operation(
 		summary = "Pending group invites",
 		responses = {
@@ -665,16 +694,16 @@ public class GroupsResource {
 		}
 	)
 	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<GroupInviteData> getInvites(@PathParam("groupname") String groupName) {
+	public List<GroupInviteData> getInvites(@PathParam("groupid") int groupId) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			return repository.getGroupRepository().getGroupInvites(groupName);
+			return repository.getGroupRepository().getGroupInvites(groupId);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}
 	}
 
 	@GET
-	@Path("/joinrequests/{groupname}")
+	@Path("/joinrequests/{groupid}")
 	@Operation(
 		summary = "Pending group join requests",
 		responses = {
@@ -688,16 +717,16 @@ public class GroupsResource {
 		}
 	)
 	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<GroupJoinRequestData> getJoinRequests(@PathParam("groupname") String groupName) {
+	public List<GroupJoinRequestData> getJoinRequests(@PathParam("groupid") int groupId) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			return repository.getGroupRepository().getGroupJoinRequests(groupName);
+			return repository.getGroupRepository().getGroupJoinRequests(groupId);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}
 	}
 
 	@GET
-	@Path("/bans/{groupname}")
+	@Path("/bans/{groupid}")
 	@Operation(
 		summary = "Current group join bans",
 		responses = {
@@ -711,9 +740,9 @@ public class GroupsResource {
 		}
 	)
 	@ApiErrors({ApiError.REPOSITORY_ISSUE})
-	public List<GroupBanData> getBans(@PathParam("groupname") String groupName) {
+	public List<GroupBanData> getBans(@PathParam("groupid") int groupId) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			return repository.getGroupRepository().getGroupBans(groupName);
+			return repository.getGroupRepository().getGroupBans(groupId);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}

src/main/java/org/qora/data/group/GroupAdminData.java

@@ -9,12 +9,12 @@ import javax.xml.bind.annotation.XmlTransient;
 public class GroupAdminData {
 
 	// Properties
-	private String groupName;
+	private int groupId;
 	private String admin;
-	/** Reference to transaction that triggered adminship */
+	/** Reference to transaction that triggered adminship. Could be JOIN_GROUP, GROUP_INVITE, CREATE_GROUP or others... */
 	// No need to ever expose this via API
 	@XmlTransient
-	private byte[] groupReference;
+	private byte[] reference;
 
 	// Constructors
 
@@ -22,28 +22,28 @@ public class GroupAdminData {
 	protected GroupAdminData() {
 	}
 
-	public GroupAdminData(String groupName, String admin, byte[] groupReference) {
+	public GroupAdminData(int groupId, String admin, byte[] reference) {
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.admin = admin;
-		this.groupReference = groupReference;
+		this.reference = reference;
 	}
 
 	// Getters / setters
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getAdmin() {
 		return this.admin;
 	}
 
-	public byte[] getGroupReference() {
+	public byte[] getReference() {
-		return this.groupReference;
+		return this.reference;
 	}
 
-	public void setGroupReference(byte[] groupReference) {
+	public void setReference(byte[] reference) {
-		this.groupReference = groupReference;
+		this.reference = reference;
 	}
 
 }

src/main/java/org/qora/data/group/GroupBanData.java

@@ -9,12 +9,13 @@ import javax.xml.bind.annotation.XmlTransient;
 public class GroupBanData {
 
 	// Properties
-	private String groupName;
+	private int groupId;
 	private String offender;
 	private String admin;
 	private long banned;
 	private String reason;
 	private Long expiry;
+	/** Reference to GROUP_BAN transaction, used to rebuild this ban during orphaning. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] reference;
@@ -25,8 +26,8 @@ public class GroupBanData {
 	protected GroupBanData() {
 	}
 
-	public GroupBanData(String groupName, String offender, String admin, long banned, String reason, Long expiry, byte[] reference) {
+	public GroupBanData(int groupId, String offender, String admin, long banned, String reason, Long expiry, byte[] reference) {
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.offender = offender;
 		this.admin = admin;
 		this.banned = banned;
@@ -37,8 +38,8 @@ public class GroupBanData {
 
 	// Getters / setters
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getOffender() {

src/main/java/org/qora/data/group/GroupData.java

@@ -9,13 +9,14 @@ import javax.xml.bind.annotation.XmlTransient;
 public class GroupData {
 
 	// Properties
+	private Integer groupId;
 	private String owner;
 	private String groupName;
 	private String description;
 	private long created;
 	private Long updated;
 	private boolean isOpen;
-	/** Reference to transaction that created group */
+	/** Reference to CREATE_GROUP or UPDATE_GROUP transaction, used to rebuild group during orphaning. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] reference;
@@ -26,7 +27,9 @@ public class GroupData {
 	protected GroupData() {
 	}
 
-	public GroupData(String owner, String name, String description, long created, Long updated, boolean isOpen, byte[] reference) {
+	/** Constructs new GroupData with nullable groupId and nullable updated [timestamp] */
+	public GroupData(Integer groupId, String owner, String name, String description, long created, Long updated, boolean isOpen, byte[] reference) {
+		this.groupId = groupId;
 		this.owner = owner;
 		this.groupName = name;
 		this.description = description;
@@ -36,12 +39,21 @@ public class GroupData {
 		this.reference = reference;
 	}
 
+	/** Constructs new GroupData with unassigned groupId */
 	public GroupData(String owner, String name, String description, long created, boolean isOpen, byte[] reference) {
-		this(owner, name, description, created, null, isOpen, reference);
+		this(null, owner, name, description, created, null, isOpen, reference);
 	}
 
 	// Getters / setters
 
+	public Integer getGroupId() {
+		return this.groupId;
+	}
+
+	public void setGroupId(Integer groupId) {
+		this.groupId = groupId;
+	}
+
 	public String getOwner() {
 		return this.owner;
 	}

src/main/java/org/qora/data/group/GroupInviteData.java

@@ -9,10 +9,11 @@ import javax.xml.bind.annotation.XmlTransient;
 public class GroupInviteData {
 
 	// Properties
-	private String groupName;
+	private int groupId;
 	private String inviter;
 	private String invitee;
 	private Long expiry;
+	/** Reference to GROUP_INVITE transaction, used to rebuild this invite during orphaning. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] reference;
@@ -23,8 +24,8 @@ public class GroupInviteData {
 	protected GroupInviteData() {
 	}
 
-	public GroupInviteData(String groupName, String inviter, String invitee, Long expiry, byte[] reference) {
+	public GroupInviteData(int groupId, String inviter, String invitee, Long expiry, byte[] reference) {
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.inviter = inviter;
 		this.invitee = invitee;
 		this.expiry = expiry;
@@ -33,8 +34,8 @@ public class GroupInviteData {
 
 	// Getters / setters
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getInviter() {

src/main/java/org/qora/data/group/GroupJoinRequestData.java

@@ -2,14 +2,19 @@ package org.qora.data.group;
 
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlTransient;
 
 // All properties to be converted to JSON via JAX-RS
 @XmlAccessorType(XmlAccessType.FIELD)
 public class GroupJoinRequestData {
 
 	// Properties
-	private String groupName;
+	private int groupId;
 	private String joiner;
+	/** Reference to JOIN_GROUP transaction, used to rebuild this join request during orphaning. */
+	// No need to ever expose this via API
+	@XmlTransient
+	private byte[] reference;
 
 	// Constructors
 
@@ -17,19 +22,28 @@ public class GroupJoinRequestData {
 	protected GroupJoinRequestData() {
 	}
 
-	public GroupJoinRequestData(String groupName, String joiner) {
+	public GroupJoinRequestData(int groupId, String joiner, byte[] reference) {
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.joiner = joiner;
+		this.reference = reference;
 	}
 
 	// Getters / setters
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getJoiner() {
 		return this.joiner;
 	}
 
+	public byte[] getReference() {
+		return this.reference;
+	}
+
+	public void setReference(byte[] reference) {
+		this.reference = reference;
+	}
+
 }

src/main/java/org/qora/data/group/GroupMemberData.java

@@ -9,13 +9,13 @@ import javax.xml.bind.annotation.XmlTransient;
 public class GroupMemberData {
 
 	// Properties
-	private String groupName;
+	private int groupId;
 	private String member;
 	private long joined;
-	/** Reference to transaction that triggered membership */
+	/** Reference to transaction that triggered membership. Could be JOIN_GROUP, GROUP_INVITE, CREATE_GROUP or others... */
 	// No need to ever expose this via API
 	@XmlTransient
-	private byte[] groupReference;
+	private byte[] reference;
 
 	// Constructors
 
@@ -23,17 +23,17 @@ public class GroupMemberData {
 	protected GroupMemberData() {
 	}
 
-	public GroupMemberData(String groupName, String member, long joined, byte[] groupReference) {
+	public GroupMemberData(int groupId, String member, long joined, byte[] reference) {
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.member = member;
 		this.joined = joined;
-		this.groupReference = groupReference;
+		this.reference = reference;
 	}
 
 	// Getters / setters
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getMember() {
@@ -44,12 +44,12 @@ public class GroupMemberData {
 		return this.joined;
 	}
 
-	public byte[] getGroupReference() {
+	public byte[] getReference() {
-		return this.groupReference;
+		return this.reference;
 	}
 
-	public void setGroupReference(byte[] groupReference) {
+	public void setReference(byte[] reference) {
-		this.groupReference = groupReference;
+		this.reference = reference;
 	}
 
 }

src/main/java/org/qora/data/transaction/AddGroupAdminTransactionData.java

@@ -18,8 +18,8 @@ public class AddGroupAdminTransactionData extends TransactionData {
 	// Properties
 	@Schema(description = "group owner's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
 	private byte[] ownerPublicKey;
-	@Schema(description = "group name", example = "my-group")
+	@Schema(description = "group ID")
-	private String groupName;
+	private int groupId;
 	@Schema(description = "member to promote to admin", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
 	private String member; 
 
@@ -34,26 +34,22 @@ public class AddGroupAdminTransactionData extends TransactionData {
 		this.creatorPublicKey = this.ownerPublicKey;
 	}
 
-	public AddGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String member, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public AddGroupAdminTransactionData(byte[] ownerPublicKey, int groupId, String member, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.ADD_GROUP_ADMIN, fee, ownerPublicKey, timestamp, reference, signature);
 
 		this.ownerPublicKey = ownerPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.member = member;
 	}
 
-	public AddGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String member, BigDecimal fee, long timestamp, byte[] reference) {
-		this(ownerPublicKey, groupName, member, fee, timestamp, reference, null);
-	}
-
 	// Getters / setters
 
 	public byte[] getOwnerPublicKey() {
 		return this.ownerPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getMember() {

src/main/java/org/qora/data/transaction/CancelGroupBanTransactionData.java

@@ -0,0 +1,78 @@
+package org.qora.data.transaction;
+
+import java.math.BigDecimal;
+
+import javax.xml.bind.Unmarshaller;
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlTransient;
+
+import org.qora.transaction.Transaction.TransactionType;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+// All properties to be converted to JSON via JAX-RS
+@XmlAccessorType(XmlAccessType.FIELD)
+@Schema(allOf = { TransactionData.class })
+public class CancelGroupBanTransactionData extends TransactionData {
+
+	// Properties
+	@Schema(description = "admin's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	private byte[] adminPublicKey;
+	@Schema(description = "group ID")
+	private int groupId;
+	@Schema(description = "member to unban from group", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
+	private String member;
+	/** Reference to GROUP_BAN transaction, used to rebuild ban during orphaning. */
+	// No need to ever expose this via API
+	@XmlTransient
+	private byte[] banReference;
+
+	// Constructors
+
+	// For JAX-RS
+	protected CancelGroupBanTransactionData() {
+		super(TransactionType.CANCEL_GROUP_BAN);
+	}
+
+	public void afterUnmarshal(Unmarshaller u, Object parent) {
+		this.creatorPublicKey = this.adminPublicKey;
+	}
+
+	public CancelGroupBanTransactionData(byte[] adminPublicKey, int groupId, String member, byte[] banReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+		super(TransactionType.CANCEL_GROUP_BAN, fee, adminPublicKey, timestamp, reference, signature);
+
+		this.adminPublicKey = adminPublicKey;
+		this.groupId = groupId;
+		this.member = member;
+		this.banReference = banReference;
+	}
+
+	/** Constructor typically used after deserialization */
+	public CancelGroupBanTransactionData(byte[] adminPublicKey, int groupId, String member, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+		this(adminPublicKey, groupId, member, null, fee, timestamp, reference, signature);
+	}
+
+	// Getters / setters
+
+	public byte[] getAdminPublicKey() {
+		return this.adminPublicKey;
+	}
+
+	public int getGroupId() {
+		return this.groupId;
+	}
+
+	public String getMember() {
+		return this.member;
+	}
+
+	public byte[] getBanReference() {
+		return this.banReference;
+	}
+
+	public void setBanReference(byte[] banReference) {
+		this.banReference = banReference;
+	}
+
+}

src/main/java/org/qora/data/transaction/CancelGroupInviteTransactionData.java

@@ -19,13 +19,14 @@ public class CancelGroupInviteTransactionData extends TransactionData {
 	// Properties
 	@Schema(description = "admin's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
 	private byte[] adminPublicKey;
-	@Schema(description = "group name", example = "my-group")
+	@Schema(description = "group ID")
-	private String groupName;
+	private int groupId;
 	@Schema(description = "invitee's address", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
 	private String invitee;
+	/** Reference to GROUP_INVITE transaction, used to rebuild invite during orphaning. */
 	// No need to ever expose this via API
 	@XmlTransient
-	private byte[] groupReference;
+	private byte[] inviteReference;
 
 	// Constructors
 
@@ -38,25 +39,18 @@ public class CancelGroupInviteTransactionData extends TransactionData {
 		this.creatorPublicKey = this.adminPublicKey;
 	}
 
-	public CancelGroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public CancelGroupInviteTransactionData(byte[] adminPublicKey, int groupId, String invitee, byte[] inviteReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.CANCEL_GROUP_INVITE, fee, adminPublicKey, timestamp, reference, signature);
 
 		this.adminPublicKey = adminPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.invitee = invitee;
-		this.groupReference = groupReference;
+		this.inviteReference = inviteReference;
 	}
 
-	public CancelGroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference) {
+	/** Constructor typically used after deserialization */
-		this(adminPublicKey, groupName, invitee, groupReference, fee, timestamp, reference, null);
+	public CancelGroupInviteTransactionData(byte[] adminPublicKey, int groupId, String invitee, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-	}
+		this(adminPublicKey, groupId, invitee, null, fee, timestamp, reference, signature);
-
-	public CancelGroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-		this(adminPublicKey, groupName, invitee, null, fee, timestamp, reference, signature);
-	}
-
-	public CancelGroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, invitee, null, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -65,20 +59,20 @@ public class CancelGroupInviteTransactionData extends TransactionData {
 		return this.adminPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getInvitee() {
 		return this.invitee;
 	}
 
-	public byte[] getGroupReference() {
+	public byte[] getInviteReference() {
-		return this.groupReference;
+		return this.inviteReference;
 	}
 
-	public void setGroupReference(byte[] groupReference) {
+	public void setInviteReference(byte[] inviteReference) {
-		this.groupReference = groupReference;
+		this.inviteReference = inviteReference;
 	}
 
 }

src/main/java/org/qora/data/transaction/CreateGroupTransactionData.java

@@ -9,19 +9,43 @@ import javax.xml.bind.annotation.XmlElement;
 import org.qora.transaction.Transaction.TransactionType;
 
 import io.swagger.v3.oas.annotations.media.Schema;
+import io.swagger.v3.oas.annotations.media.Schema.AccessMode;
 
 // All properties to be converted to JSON via JAX-RS
 @XmlAccessorType(XmlAccessType.FIELD)
-@Schema(allOf = { TransactionData.class })
+@Schema(
+	allOf = {
+		TransactionData.class
+	}
+)
 public class CreateGroupTransactionData extends TransactionData {
 
-	@Schema(description = "group owner's address", example = "QgV4s3xnzLhVBEJxcYui4u4q11yhUHsd9v")
+	// Properties
+	// groupId can be null but assigned during save() or during load from repository
+	@Schema(
+		accessMode = AccessMode.READ_ONLY,
+		description = "assigned group ID"
+	)
+	private Integer groupId = null;
+	@Schema(
+		description = "group owner's address",
+		example = "QgV4s3xnzLhVBEJxcYui4u4q11yhUHsd9v"
+	)
 	private String owner;
-	@Schema(description = "group name", example = "miner-group")
+	@Schema(
+		description = "group name",
+		example = "miner-group"
+	)
 	private String groupName;
-	@Schema(description = "short description of group", example = "this group is for block miners")
+	@Schema(
+		description = "short description of group",
+		example = "this group is for block miners"
+	)
 	private String description;
-	@Schema(description = "whether anyone can join group (open) or group is invite-only (closed)", example = "true")
+	@Schema(
+		description = "whether anyone can join group (open) or group is invite-only (closed)",
+		example = "true"
+	)
 	private boolean isOpen;
 
 	// Constructors
@@ -31,8 +55,8 @@ public class CreateGroupTransactionData extends TransactionData {
 		super(TransactionType.CREATE_GROUP);
 	}
 
-	public CreateGroupTransactionData(byte[] creatorPublicKey, String owner, String groupName, String description, boolean isOpen, BigDecimal fee, long timestamp, byte[] reference,
+	public CreateGroupTransactionData(byte[] creatorPublicKey, String owner, String groupName, String description, boolean isOpen, Integer groupId,
-			byte[] signature) {
+			BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.CREATE_GROUP, fee, creatorPublicKey, timestamp, reference, signature);
 
 		this.creatorPublicKey = creatorPublicKey;
@@ -40,10 +64,7 @@ public class CreateGroupTransactionData extends TransactionData {
 		this.groupName = groupName;
 		this.description = description;
 		this.isOpen = isOpen;
-	}
+		this.groupId = groupId;
-
-	public CreateGroupTransactionData(byte[] creatorPublicKey, String owner, String groupName, String description, boolean isOpen, BigDecimal fee, long timestamp, byte[] reference) {
-		this(creatorPublicKey, owner, groupName, description, isOpen, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -64,15 +85,35 @@ public class CreateGroupTransactionData extends TransactionData {
 		return this.isOpen;
 	}
 
+	public Integer getGroupId() {
+		return this.groupId;
+	}
+
+	public void setGroupId(Integer groupId) {
+		this.groupId = groupId;
+	}
+
 	// Re-expose creatorPublicKey for this transaction type for JAXB
-	@XmlElement(name = "creatorPublicKey")
+	@XmlElement(
-	@Schema(name = "creatorPublicKey", description = "group creator's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+		name = "creatorPublicKey"
+	)
+	@Schema(
+		name = "creatorPublicKey",
+		description = "group creator's public key",
+		example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP"
+	)
 	public byte[] getGroupCreatorPublicKey() {
 		return this.creatorPublicKey;
 	}
 
-	@XmlElement(name = "creatorPublicKey")
+	@XmlElement(
-	@Schema(name = "creatorPublicKey", description = "group creator's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+		name = "creatorPublicKey"
+	)
+	@Schema(
+		name = "creatorPublicKey",
+		description = "group creator's public key",
+		example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP"
+	)
 	public void setGroupCreatorPublicKey(byte[] creatorPublicKey) {
 		this.creatorPublicKey = creatorPublicKey;
 	}

src/main/java/org/qora/data/transaction/GroupBanTransactionData.java

@@ -13,26 +13,48 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 // All properties to be converted to JSON via JAX-RS
 @XmlAccessorType(XmlAccessType.FIELD)
-@Schema(allOf = { TransactionData.class })
+@Schema(
+	allOf = {
+		TransactionData.class
+	}
+)
 public class GroupBanTransactionData extends TransactionData {
 
 	// Properties
-	@Schema(description = "admin's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	@Schema(
+		description = "admin's public key",
+		example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP"
+	)
 	private byte[] adminPublicKey;
-	@Schema(description = "group name", example = "my-group")
+	@Schema(
-	private String groupName;
+		description = "group ID"
-	@Schema(description = "offender to ban from group", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
+	)
+	private int groupId;
+	@Schema(
+		description = "offender to ban from group",
+		example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK"
+	)
 	private String offender;
-	@Schema(description = "reason for ban")
+	@Schema(
+		description = "reason for ban"
+	)
 	private String reason;
-	@Schema(description = "ban lifetime in seconds")
+	@Schema(
+		description = "ban lifetime in seconds"
+	)
 	private int timeToLive;
+	/** Reference to transaction that triggered membership. Could be JOIN_GROUP, GROUP_INVITE or UPDATE_GROUP transaction. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] memberReference;
+	/** Reference to transaction that triggered adminship. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] adminReference;
+	/** Reference to pending join-request or invite transaction that was deleted by this so it (invite/join-request) can be rebuilt during orphaning. */
+	// No need to ever expose this via API
+	@XmlTransient
+	private byte[] joinInviteReference;
 
 	// Constructors
 
@@ -45,28 +67,24 @@ public class GroupBanTransactionData extends TransactionData {
 		this.creatorPublicKey = this.adminPublicKey;
 	}
 
-	public GroupBanTransactionData(byte[] adminPublicKey, String groupName, String member, String reason, int timeToLive, byte[] memberReference, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public GroupBanTransactionData(byte[] adminPublicKey, int groupId, String member, String reason, int timeToLive, byte[] memberReference,
+			byte[] adminReference, byte[] joinInviteReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.GROUP_BAN, fee, adminPublicKey, timestamp, reference, signature);
 
 		this.adminPublicKey = adminPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.offender = member;
 		this.reason = reason;
 		this.timeToLive = timeToLive;
 		this.memberReference = memberReference;
 		this.adminReference = adminReference;
+		this.joinInviteReference = joinInviteReference;
 	}
 
-	public GroupBanTransactionData(byte[] adminPublicKey, String groupName, String offender, String reason, int timeToLive, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	/** Constructor typically used after deserialization */
-		this(adminPublicKey, groupName, offender, reason, timeToLive, null, null, fee, timestamp, reference, signature);
+	public GroupBanTransactionData(byte[] adminPublicKey, int groupId, String offender, String reason, int timeToLive, BigDecimal fee, long timestamp,
-	}
+			byte[] reference, byte[] signature) {
-
+		this(adminPublicKey, groupId, offender, reason, timeToLive, null, null, null, fee, timestamp, reference, signature);
-	public GroupBanTransactionData(byte[] adminPublicKey, String groupName, String offender, String reason, int timeToLive, byte[] memberReference, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, offender, reason, timeToLive, memberReference, adminReference, fee, timestamp, reference, null);
-	}
-
-	public GroupBanTransactionData(byte[] adminPublicKey, String groupName, String offender, String reason, int timeToLive, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, offender, reason, timeToLive, null, null, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -75,8 +93,8 @@ public class GroupBanTransactionData extends TransactionData {
 		return this.adminPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getOffender() {
@@ -107,4 +125,12 @@ public class GroupBanTransactionData extends TransactionData {
 		this.adminReference = adminReference;
 	}
 
+	public byte[] getJoinInviteReference() {
+		return this.joinInviteReference;
+	}
+
+	public void setJoinInviteReference(byte[] reference) {
+		this.joinInviteReference = reference;
+	}
+
 }

src/main/java/org/qora/data/transaction/GroupInviteTransactionData.java

@@ -19,15 +19,16 @@ public class GroupInviteTransactionData extends TransactionData {
 	// Properties
 	@Schema(description = "admin's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
 	private byte[] adminPublicKey;
-	@Schema(description = "group name", example = "my-group")
+	@Schema(description = "group ID")
-	private String groupName;
+	private int groupId;
 	@Schema(description = "invitee's address", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
 	private String invitee;
 	@Schema(description = "invitation lifetime in seconds")
 	private int timeToLive;
+	/** Reference to JOIN_GROUP transaction, used to rebuild this join request during orphaning. */
 	// No need to ever expose this via API
 	@XmlTransient
-	private byte[] groupReference;
+	private byte[] joinReference;
 
 	// Constructors
 
@@ -40,26 +41,19 @@ public class GroupInviteTransactionData extends TransactionData {
 		this.creatorPublicKey = this.adminPublicKey;
 	}
 
-	public GroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, int timeToLive, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public GroupInviteTransactionData(byte[] adminPublicKey, int groupId, String invitee, int timeToLive, byte[] joinReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.GROUP_INVITE, fee, adminPublicKey, timestamp, reference, signature);
 
 		this.adminPublicKey = adminPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.invitee = invitee;
 		this.timeToLive = timeToLive;
-		this.groupReference = groupReference;
+		this.joinReference = joinReference;
 	}
 
-	public GroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, int timeToLive, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference) {
+	/** Constructor typically used after deserialization */
-		this(adminPublicKey, groupName, invitee, timeToLive, groupReference, fee, timestamp, reference, null);
+	public GroupInviteTransactionData(byte[] adminPublicKey, int groupId, String invitee, int timeToLive, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-	}
+		this(adminPublicKey, groupId, invitee, timeToLive, null, fee, timestamp, reference, signature);
-
-	public GroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, int timeToLive, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-		this(adminPublicKey, groupName, invitee, timeToLive, null, fee, timestamp, reference, signature);
-	}
-
-	public GroupInviteTransactionData(byte[] adminPublicKey, String groupName, String invitee, int timeToLive, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, invitee, timeToLive, null, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -68,8 +62,8 @@ public class GroupInviteTransactionData extends TransactionData {
 		return this.adminPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getInvitee() {
@@ -80,12 +74,12 @@ public class GroupInviteTransactionData extends TransactionData {
 		return this.timeToLive;
 	}
 
-	public byte[] getGroupReference() {
+	public byte[] getJoinReference() {
-		return this.groupReference;
+		return this.joinReference;
 	}
 
-	public void setGroupReference(byte[] groupReference) {
+	public void setJoinReference(byte[] joinReference) {
-		this.groupReference = groupReference;
+		this.joinReference = joinReference;
 	}
 
 }

src/main/java/org/qora/data/transaction/GroupKickTransactionData.java

@@ -13,24 +13,45 @@ import io.swagger.v3.oas.annotations.media.Schema;
 
 // All properties to be converted to JSON via JAX-RS
 @XmlAccessorType(XmlAccessType.FIELD)
-@Schema(allOf = { TransactionData.class })
+@Schema(
+	allOf = {
+		TransactionData.class
+	}
+)
 public class GroupKickTransactionData extends TransactionData {
 
 	// Properties
-	@Schema(description = "admin's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	@Schema(
+		description = "admin's public key",
+		example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP"
+	)
 	private byte[] adminPublicKey;
-	@Schema(description = "group name", example = "my-group")
+	@Schema(
-	private String groupName;
+		description = "group name",
-	@Schema(description = "member to kick from group", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
+		example = "my-group"
+	)
+	private int groupId;
+	@Schema(
+		description = "member to kick from group",
+		example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK"
+	)
 	private String member;
-	@Schema(description = "reason for kick")
+	@Schema(
+		description = "reason for kick"
+	)
 	private String reason;
+	/** Reference to transaction that triggered membership. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] memberReference;
+	/** Reference to transaction that triggered adminship. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] adminReference;
+	/** Reference to JOIN_GROUP transaction, used to rebuild this join request during orphaning. */
+	// No need to ever expose this via API
+	@XmlTransient
+	private byte[] joinReference;
 
 	// Constructors
 
@@ -43,27 +64,23 @@ public class GroupKickTransactionData extends TransactionData {
 		this.creatorPublicKey = this.adminPublicKey;
 	}
 
-	public GroupKickTransactionData(byte[] adminPublicKey, String groupName, String member, String reason, byte[] memberReference, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public GroupKickTransactionData(byte[] adminPublicKey, int groupId, String member, String reason, byte[] memberReference, byte[] adminReference,
+			byte[] joinReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.GROUP_KICK, fee, adminPublicKey, timestamp, reference, signature);
 
 		this.adminPublicKey = adminPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.member = member;
 		this.reason = reason;
 		this.memberReference = memberReference;
 		this.adminReference = adminReference;
+		this.joinReference = joinReference;
 	}
 
-	public GroupKickTransactionData(byte[] adminPublicKey, String groupName, String member, String reason, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	/** Constructor typically used after deserialization */
-		this(adminPublicKey, groupName, member, reason, null, null, fee, timestamp, reference, signature);
+	public GroupKickTransactionData(byte[] adminPublicKey, int groupId, String member, String reason, BigDecimal fee, long timestamp, byte[] reference,
-	}
+			byte[] signature) {
-
+		this(adminPublicKey, groupId, member, reason, null, null, null, fee, timestamp, reference, signature);
-	public GroupKickTransactionData(byte[] adminPublicKey, String groupName, String member, String reason, byte[] memberReference, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, member, reason, memberReference, adminReference, fee, timestamp, reference, null);
-	}
-
-	public GroupKickTransactionData(byte[] adminPublicKey, String groupName, String member, String reason, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, member, reason, null, null, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -72,8 +89,8 @@ public class GroupKickTransactionData extends TransactionData {
 		return this.adminPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getMember() {
@@ -100,4 +117,12 @@ public class GroupKickTransactionData extends TransactionData {
 		this.adminReference = adminReference;
 	}
 
+	public byte[] getJoinReference() {
+		return this.joinReference;
+	}
+
+	public void setJoinReference(byte[] joinReference) {
+		this.joinReference = joinReference;
+	}
+
 }

src/main/java/org/qora/data/transaction/GroupUnbanTransactionData.java

@@ -1,84 +0,0 @@
-package org.qora.data.transaction;
-
-import java.math.BigDecimal;
-
-import javax.xml.bind.Unmarshaller;
-import javax.xml.bind.annotation.XmlAccessType;
-import javax.xml.bind.annotation.XmlAccessorType;
-import javax.xml.bind.annotation.XmlTransient;
-
-import org.qora.transaction.Transaction.TransactionType;
-
-import io.swagger.v3.oas.annotations.media.Schema;
-
-// All properties to be converted to JSON via JAX-RS
-@XmlAccessorType(XmlAccessType.FIELD)
-@Schema(allOf = { TransactionData.class })
-public class GroupUnbanTransactionData extends TransactionData {
-
-	// Properties
-	@Schema(description = "admin's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
-	private byte[] adminPublicKey;
-	@Schema(description = "group name", example = "my-group")
-	private String groupName;
-	@Schema(description = "member to unban from group", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
-	private String member;
-	// No need to ever expose this via API
-	@XmlTransient
-	private byte[] groupReference;
-
-	// Constructors
-
-	// For JAX-RS
-	protected GroupUnbanTransactionData() {
-		super(TransactionType.GROUP_UNBAN);
-	}
-
-	public void afterUnmarshal(Unmarshaller u, Object parent) {
-		this.creatorPublicKey = this.adminPublicKey;
-	}
-
-	public GroupUnbanTransactionData(byte[] adminPublicKey, String groupName, String member, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-		super(TransactionType.GROUP_UNBAN, fee, adminPublicKey, timestamp, reference, signature);
-
-		this.adminPublicKey = adminPublicKey;
-		this.groupName = groupName;
-		this.member = member;
-		this.groupReference = groupReference;
-	}
-
-	public GroupUnbanTransactionData(byte[] adminPublicKey, String groupName, String member, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, member, groupReference, fee, timestamp, reference, null);
-	}
-
-	public GroupUnbanTransactionData(byte[] adminPublicKey, String groupName, String member, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-		this(adminPublicKey, groupName, member, null, fee, timestamp, reference, signature);
-	}
-
-	public GroupUnbanTransactionData(byte[] adminPublicKey, String groupName, String member, BigDecimal fee, long timestamp, byte[] reference) {
-		this(adminPublicKey, groupName, member, null, fee, timestamp, reference, null);
-	}
-
-	// Getters / setters
-
-	public byte[] getAdminPublicKey() {
-		return this.adminPublicKey;
-	}
-
-	public String getGroupName() {
-		return this.groupName;
-	}
-
-	public String getMember() {
-		return this.member;
-	}
-
-	public byte[] getGroupReference() {
-		return this.groupReference;
-	}
-
-	public void setGroupReference(byte[] groupReference) {
-		this.groupReference = groupReference;
-	}
-
-}

src/main/java/org/qora/data/transaction/JoinGroupTransactionData.java

@@ -5,6 +5,7 @@ import java.math.BigDecimal;
 import javax.xml.bind.Unmarshaller;
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlTransient;
 
 import org.qora.transaction.Transaction.TransactionType;
 
@@ -19,7 +20,11 @@ public class JoinGroupTransactionData extends TransactionData {
 	@Schema(description = "joiner's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
 	private byte[] joinerPublicKey;
 	@Schema(description = "which group to join", example = "my-group")
-	private String groupName;
+	private int groupId;
+	/** Reference to GROUP_INVITE transaction, used to rebuild invite during orphaning. */
+	// No need to ever expose this via API
+	@XmlTransient
+	private byte[] inviteReference;
 
 	// Constructors
 
@@ -32,15 +37,17 @@ public class JoinGroupTransactionData extends TransactionData {
 		this.creatorPublicKey = this.joinerPublicKey;
 	}
 
-	public JoinGroupTransactionData(byte[] joinerPublicKey, String groupName, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public JoinGroupTransactionData(byte[] joinerPublicKey, int groupId, byte[] inviteReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.JOIN_GROUP, fee, joinerPublicKey, timestamp, reference, signature);
 
 		this.joinerPublicKey = joinerPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
+		this.inviteReference = inviteReference;
 	}
 
-	public JoinGroupTransactionData(byte[] joinerPublicKey, String groupName, BigDecimal fee, long timestamp, byte[] reference) {
+	/** Constructor typically used after deserialization */
-		this(joinerPublicKey, groupName, fee, timestamp, reference, null);
+	public JoinGroupTransactionData(byte[] joinerPublicKey, int groupId, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+		this(joinerPublicKey, groupId, null, fee, timestamp, reference, signature);
 	}
 
 	// Getters / setters
@@ -49,8 +56,16 @@ public class JoinGroupTransactionData extends TransactionData {
 		return this.joinerPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
+	}
+
+	public byte[] getInviteReference() {
+		return this.inviteReference;
+	}
+
+	public void setInviteReference(byte[] inviteReference) {
+		this.inviteReference = inviteReference;
 	}
 
 }

src/main/java/org/qora/data/transaction/LeaveGroupTransactionData.java

@@ -20,10 +20,12 @@ public class LeaveGroupTransactionData extends TransactionData {
 	@Schema(description = "leaver's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
 	private byte[] leaverPublicKey;
 	@Schema(description = "which group to leave", example = "my-group")
-	private String groupName;
+	private int groupId;
+	/** Reference to transaction that triggered membership. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] memberReference;
+	/** Reference to transaction that triggered adminship. */
 	// No need to ever expose this via API
 	@XmlTransient
 	private byte[] adminReference;
@@ -39,25 +41,18 @@ public class LeaveGroupTransactionData extends TransactionData {
 		this.creatorPublicKey = this.leaverPublicKey;
 	}
 
-	public LeaveGroupTransactionData(byte[] leaverPublicKey, String groupName, byte[] memberReference, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public LeaveGroupTransactionData(byte[] leaverPublicKey, int groupId, byte[] memberReference, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.LEAVE_GROUP, fee, leaverPublicKey, timestamp, reference, signature);
 
 		this.leaverPublicKey = leaverPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.memberReference = memberReference;
 		this.adminReference = adminReference;
 	}
 
-	public LeaveGroupTransactionData(byte[] leaverPublicKey, String groupName, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	/** Constructor typically used after deserialization */
-		this(leaverPublicKey, groupName, null, null, fee, timestamp, reference, signature);
+	public LeaveGroupTransactionData(byte[] leaverPublicKey, int groupId, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-	}
+		this(leaverPublicKey, groupId, null, null, fee, timestamp, reference, signature);
-
-	public LeaveGroupTransactionData(byte[] leaverPublicKey, String groupName, byte[] memberReference, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference) {
-		this(leaverPublicKey, groupName, memberReference, adminReference, fee, timestamp, reference, null);
-	}
-
-	public LeaveGroupTransactionData(byte[] leaverPublicKey, String groupName, BigDecimal fee, long timestamp, byte[] reference) {
-		this(leaverPublicKey, groupName, null, null, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -66,8 +61,8 @@ public class LeaveGroupTransactionData extends TransactionData {
 		return this.leaverPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public byte[] getMemberReference() {

src/main/java/org/qora/data/transaction/RemoveGroupAdminTransactionData.java

@@ -19,14 +19,15 @@ public class RemoveGroupAdminTransactionData extends TransactionData {
 	// Properties
 	@Schema(description = "group owner's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
 	private byte[] ownerPublicKey;
-	@Schema(description = "group name", example = "my-group")
+	@Schema(description = "group ID")
-	private String groupName;
+	private int groupId;
 	@Schema(description = "admin to demote", example = "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK")
 	private String admin; 
+	/** Reference to transaction that triggered adminship. */
 	// For internal use when orphaning
 	@XmlTransient
 	@Schema(hidden = true)
-	private byte[] groupReference;
+	private byte[] adminReference;
 
 	// Constructors
 
@@ -39,25 +40,18 @@ public class RemoveGroupAdminTransactionData extends TransactionData {
 		this.creatorPublicKey = this.ownerPublicKey;
 	}
 
-	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
+	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, int groupId, String admin, byte[] adminReference, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
 		super(TransactionType.REMOVE_GROUP_ADMIN, fee, ownerPublicKey, timestamp, reference, signature);
 
 		this.ownerPublicKey = ownerPublicKey;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.admin = admin;
-		this.groupReference = groupReference;
+		this.adminReference = adminReference;
 	}
 
-	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, byte[] groupReference, BigDecimal fee, long timestamp, byte[] reference) {
+	/** Constructor typically used after deserialization */
-		this(ownerPublicKey, groupName, admin, groupReference, fee, timestamp, reference, null);
+	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, int groupId, String admin, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-	}
+		this(ownerPublicKey, groupId, admin, null, fee, timestamp, reference, signature);
-
-	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, BigDecimal fee, long timestamp, byte[] reference, byte[] signature) {
-		this(ownerPublicKey, groupName, admin, null, fee, timestamp, reference, signature);
-	}
-
-	public RemoveGroupAdminTransactionData(byte[] ownerPublicKey, String groupName, String admin, BigDecimal fee, long timestamp, byte[] reference) {
-		this(ownerPublicKey, groupName, admin, null, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -66,20 +60,20 @@ public class RemoveGroupAdminTransactionData extends TransactionData {
 		return this.ownerPublicKey;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getAdmin() {
 		return this.admin;
 	}
 
-	public byte[] getGroupReference() {
+	public byte[] getAdminReference() {
-		return this.groupReference;
+		return this.adminReference;
 	}
 
-	public void setGroupReference(byte[] groupReference) {
+	public void setAdminReference(byte[] adminReference) {
-		this.groupReference = groupReference;
+		this.adminReference = adminReference;
 	}
 
 }

src/main/java/org/qora/data/transaction/TransactionData.java

@@ -35,7 +35,7 @@ import io.swagger.v3.oas.annotations.media.Schema.AccessMode;
 	MultiPaymentTransactionData.class, DeployATTransactionData.class, MessageTransactionData.class, ATTransactionData.class,
 	CreateGroupTransactionData.class, UpdateGroupTransactionData.class,
 	AddGroupAdminTransactionData.class, RemoveGroupAdminTransactionData.class,
-	GroupBanTransactionData.class, GroupUnbanTransactionData.class,
+	GroupBanTransactionData.class, CancelGroupBanTransactionData.class,
 	GroupKickTransactionData.class, GroupInviteTransactionData.class,
 	JoinGroupTransactionData.class, LeaveGroupTransactionData.class
 })

src/main/java/org/qora/data/transaction/UpdateGroupTransactionData.java

@@ -22,11 +22,12 @@ public class UpdateGroupTransactionData extends TransactionData {
 	@Schema(description = "new owner's address", example = "QgV4s3xnzLhVBEJxcYui4u4q11yhUHsd9v")
 	private String newOwner;
 	@Schema(description = "which group to update", example = "my-group")
-	private String groupName;
+	private int groupId;
 	@Schema(description = "replacement group description", example = "my group for accounts I like")
 	private String newDescription;
 	@Schema(description = "new group join policy", example = "true")
 	private boolean newIsOpen;
+	/** Reference to CREATE_GROUP or UPDATE_GROUP transaction, used to rebuild group during orphaning. */
 	// For internal use when orphaning
 	@XmlTransient
 	@Schema(hidden = true)
@@ -43,26 +44,22 @@ public class UpdateGroupTransactionData extends TransactionData {
 		this.creatorPublicKey = this.ownerPublicKey;
 	}
 
-	public UpdateGroupTransactionData(byte[] ownerPublicKey, String groupName, String newOwner, String newDescription, boolean newIsOpen, byte[] groupReference, BigDecimal fee, long timestamp,
+	public UpdateGroupTransactionData(byte[] ownerPublicKey, int groupId, String newOwner, String newDescription, boolean newIsOpen, byte[] groupReference, BigDecimal fee, long timestamp,
 			byte[] reference, byte[] signature) {
 		super(TransactionType.UPDATE_GROUP, fee, ownerPublicKey, timestamp, reference, signature);
 
 		this.ownerPublicKey = ownerPublicKey;
 		this.newOwner = newOwner;
-		this.groupName = groupName;
+		this.groupId = groupId;
 		this.newDescription = newDescription;
 		this.newIsOpen = newIsOpen;
 		this.groupReference = groupReference;
 	}
 
-	public UpdateGroupTransactionData(byte[] ownerPublicKey, String groupName, String newOwner, String newDescription, boolean newIsOpen, BigDecimal fee, long timestamp, byte[] reference,
+	/** Constructor typically used after deserialization */
+	public UpdateGroupTransactionData(byte[] ownerPublicKey, int groupId, String newOwner, String newDescription, boolean newIsOpen, BigDecimal fee, long timestamp, byte[] reference,
 			byte[] signature) {
-		this(ownerPublicKey, groupName, newOwner, newDescription, newIsOpen, null, fee, timestamp, reference, signature);
+		this(ownerPublicKey, groupId, newOwner, newDescription, newIsOpen, null, fee, timestamp, reference, signature);
-	}
-
-	public UpdateGroupTransactionData(byte[] ownerPublicKey, String groupName, String newOwner, String newDescription, boolean newIsOpen, byte[] groupReference, BigDecimal fee, long timestamp,
-			byte[] reference) {
-		this(ownerPublicKey, groupName, newOwner, newDescription, newIsOpen, groupReference, fee, timestamp, reference, null);
 	}
 
 	// Getters / setters
@@ -75,8 +72,8 @@ public class UpdateGroupTransactionData extends TransactionData {
 		return this.newOwner;
 	}
 
-	public String getGroupName() {
+	public int getGroupId() {
-		return this.groupName;
+		return this.groupId;
 	}
 
 	public String getNewDescription() {

src/main/java/org/qora/group/Group.java

@@ -1,7 +1,6 @@
 package org.qora.group;
 
 import java.util.Arrays;
-import java.util.List;
 
 import org.qora.account.Account;
 import org.qora.account.PublicKeyAccount;
@@ -17,7 +16,7 @@ import org.qora.data.transaction.CreateGroupTransactionData;
 import org.qora.data.transaction.GroupBanTransactionData;
 import org.qora.data.transaction.GroupInviteTransactionData;
 import org.qora.data.transaction.GroupKickTransactionData;
-import org.qora.data.transaction.GroupUnbanTransactionData;
+import org.qora.data.transaction.CancelGroupBanTransactionData;
 import org.qora.data.transaction.JoinGroupTransactionData;
 import org.qora.data.transaction.LeaveGroupTransactionData;
 import org.qora.data.transaction.RemoveGroupAdminTransactionData;
@@ -31,13 +30,14 @@ public class Group {
 
 	// Properties
 	private Repository repository;
+	private GroupRepository groupRepository;
 	private GroupData groupData;
 
 	// Useful constants
-	public static final int MAX_NAME_SIZE = 400;
+	public static final int MAX_NAME_SIZE = 32;
-	public static final int MAX_DESCRIPTION_SIZE = 4000;
+	public static final int MAX_DESCRIPTION_SIZE = 128;
 	/** Max size of kick/ban reason */
-	public static final int MAX_REASON_SIZE = 400;
+	public static final int MAX_REASON_SIZE = 128;
 
 	// Constructors
 
@@ -49,6 +49,8 @@ public class Group {
 	 */
 	public Group(Repository repository, CreateGroupTransactionData createGroupTransactionData) {
 		this.repository = repository;
+		this.groupRepository = repository.getGroupRepository();
+
 		this.groupData = new GroupData(createGroupTransactionData.getOwner(), createGroupTransactionData.getGroupName(),
 				createGroupTransactionData.getDescription(), createGroupTransactionData.getTimestamp(), createGroupTransactionData.getIsOpen(),
 				createGroupTransactionData.getSignature());
@@ -58,16 +60,151 @@ public class Group {
 	 * Construct Group business object using existing group in repository.
 	 * 
 	 * @param repository
-	 * @param groupName
+	 * @param groupId
 	 * @throws DataException
 	 */
-	public Group(Repository repository, String groupName) throws DataException {
+	public Group(Repository repository, int groupId) throws DataException {
 		this.repository = repository;
-		this.groupData = this.repository.getGroupRepository().fromGroupName(groupName);
+		this.groupRepository = repository.getGroupRepository();
+
+		this.groupData = this.repository.getGroupRepository().fromGroupId(groupId);
+	}
+
+	// Getters / setters
+
+	public GroupData getGroupData() {
+		return this.groupData;
+	}
+
+	// Shortcuts to aid code clarity
+
+	// Membership
+
+	private GroupMemberData getMember(String member) throws DataException {
+		return groupRepository.getMember(this.groupData.getGroupId(), member);
+	}
+
+	private boolean memberExists(String member) throws DataException {
+		return groupRepository.memberExists(this.groupData.getGroupId(), member);
+	}
+
+	private void addMember(String member, long joined, byte[] reference) throws DataException {
+		GroupMemberData groupMemberData = new GroupMemberData(this.groupData.getGroupId(), member, joined, reference);
+		groupRepository.save(groupMemberData);
+	}
+
+	private void addMember(String member, TransactionData transactionData) throws DataException {
+		this.addMember(member, transactionData.getTimestamp(), transactionData.getSignature());
+	}
+
+	private void rebuildMember(String member, byte[] reference) throws DataException {
+		TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(reference);
+		this.addMember(member, transactionData);
+	}
+
+	private void deleteMember(String member) throws DataException {
+		groupRepository.deleteMember(this.groupData.getGroupId(), member);
+	}
+
+	// Adminship
+
+	private GroupAdminData getAdmin(String admin) throws DataException {
+		return groupRepository.getAdmin(this.groupData.getGroupId(), admin);
+	}
+
+	private boolean adminExists(String admin) throws DataException {
+		return groupRepository.adminExists(this.groupData.getGroupId(), admin);
+	}
+
+	private void addAdmin(String admin, byte[] reference) throws DataException {
+		GroupAdminData groupAdminData = new GroupAdminData(this.groupData.getGroupId(), admin, reference);
+		groupRepository.save(groupAdminData);
+	}
+
+	private void addAdmin(String admin, TransactionData transactionData) throws DataException {
+		this.addAdmin(admin, transactionData.getSignature());
+	}
+
+	private void rebuildAdmin(String admin, byte[] reference) throws DataException {
+		TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(reference);
+		this.addAdmin(admin, transactionData);
+	}
+
+	private void deleteAdmin(String admin) throws DataException {
+		groupRepository.deleteAdmin(this.groupData.getGroupId(), admin);
+	}
+
+	// Join request
+
+	private GroupJoinRequestData getJoinRequest(String joiner) throws DataException {
+		return groupRepository.getJoinRequest(this.groupData.getGroupId(), joiner);
+	}
+
+	private void addJoinRequest(String joiner, byte[] reference) throws DataException {
+		GroupJoinRequestData groupJoinRequestData = new GroupJoinRequestData(this.groupData.getGroupId(), joiner, reference);
+		groupRepository.save(groupJoinRequestData);
+	}
+
+	private void rebuildJoinRequest(String joiner, byte[] reference) throws DataException {
+		this.addJoinRequest(joiner, reference);
+	}
+
+	private void deleteJoinRequest(String joiner) throws DataException {
+		groupRepository.deleteJoinRequest(this.groupData.getGroupId(), joiner);
+	}
+
+	// Invites
+
+	private GroupInviteData getInvite(String invitee) throws DataException {
+		return groupRepository.getInvite(this.groupData.getGroupId(), invitee);
+	}
+
+	private void addInvite(GroupInviteTransactionData groupInviteTransactionData) throws DataException {
+		Account inviter = new PublicKeyAccount(this.repository, groupInviteTransactionData.getAdminPublicKey());
+		String invitee = groupInviteTransactionData.getInvitee();
+		Long expiry = null;
+		int timeToLive = groupInviteTransactionData.getTimeToLive();
+		if (timeToLive != 0)
+			expiry = groupInviteTransactionData.getTimestamp() + timeToLive * 1000;
+
+		GroupInviteData groupInviteData = new GroupInviteData(this.groupData.getGroupId(), inviter.getAddress(), invitee, expiry,
+				groupInviteTransactionData.getSignature());
+		groupRepository.save(groupInviteData);
+	}
+
+	private void rebuildInvite(String invitee, byte[] reference) throws DataException {
+		TransactionData previousTransactionData = this.repository.getTransactionRepository().fromSignature(reference);
+		this.addInvite((GroupInviteTransactionData) previousTransactionData);
+	}
+
+	private void deleteInvite(String invitee) throws DataException {
+		groupRepository.deleteInvite(this.groupData.getGroupId(), invitee);
+	}
+
+	// Bans
+
+	private void addBan(GroupBanTransactionData groupBanTransactionData) throws DataException {
+		String offender = groupBanTransactionData.getOffender();
+		Account admin = new PublicKeyAccount(this.repository, groupBanTransactionData.getAdminPublicKey());
+		long banned = groupBanTransactionData.getTimestamp();
+		String reason = groupBanTransactionData.getReason();
+
+		Long expiry = null;
+		int timeToLive = groupBanTransactionData.getTimeToLive();
+		if (timeToLive != 0)
+			expiry = groupBanTransactionData.getTimestamp() + timeToLive * 1000;
+
+		// Save reference to this banning transaction so cancel-ban can rebuild ban during orphaning.
+		byte[] reference = groupBanTransactionData.getSignature();
+
+		GroupBanData groupBanData = new GroupBanData(this.groupData.getGroupId(), offender, admin.getAddress(), banned, reason, expiry, reference);
+		groupRepository.save(groupBanData);
 	}
 
 	// Processing
 
+	// "un"-methods are the orphaning versions. e.g. "uncreate" undoes "create" processing.
+
 	/*
 	 * GroupData records can be changed by CREATE_GROUP or UPDATE_GROUP transactions.
 	 * 
@@ -75,7 +212,8 @@ public class Group {
 	 * in a field called "reference".
 	 * 
 	 * During orphaning, "reference" is used to fetch the previous GroupData-changing transaction
-	 * and that transaction's contents are used to restore the previous GroupData state.
+	 * and that transaction's contents are used to restore the previous GroupData state,
+	 * including GroupData's previous "reference" value.
 	 */
 
 	// CREATE GROUP
@@ -84,19 +222,16 @@ public class Group {
 		// Note: this.groupData already populated by our constructor above
 		this.repository.getGroupRepository().save(this.groupData);
 
-		// Add owner as admin
-		GroupAdminData groupAdminData = new GroupAdminData(this.groupData.getGroupName(), this.groupData.getOwner(), createGroupTransactionData.getSignature());
-		this.repository.getGroupRepository().save(groupAdminData);
-
 		// Add owner as member
-		GroupMemberData groupMemberData = new GroupMemberData(this.groupData.getGroupName(), this.groupData.getOwner(), this.groupData.getCreated(),
+		this.addMember(this.groupData.getOwner(), createGroupTransactionData);
-				createGroupTransactionData.getSignature());
+
-		this.repository.getGroupRepository().save(groupMemberData);
+		// Add owner as admin
+		this.addAdmin(this.groupData.getOwner(), createGroupTransactionData);
 	}
 
 	public void uncreate() throws DataException {
 		// Repository takes care of cleaning up ancilliary data!
-		this.repository.getGroupRepository().delete(this.groupData.getGroupName());
+		this.repository.getGroupRepository().delete(this.groupData.getGroupId());
 	}
 
 	// UPDATE GROUP
@@ -108,9 +243,6 @@ public class Group {
 	 */
 
 	public void updateGroup(UpdateGroupTransactionData updateGroupTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = updateGroupTransactionData.getGroupName();
-
 		// Save GroupData's reference in our transaction data
 		updateGroupTransactionData.setGroupReference(this.groupData.getReference());
 
@@ -129,25 +261,17 @@ public class Group {
 		String newOwner = updateGroupTransactionData.getNewOwner();
 
 		// New owner should be a member if not already
-		if (!groupRepository.memberExists(groupName, newOwner)) {
+		if (!this.memberExists(newOwner))
-			GroupMemberData groupMemberData = new GroupMemberData(groupName, newOwner, updateGroupTransactionData.getTimestamp(),
+			this.addMember(newOwner, updateGroupTransactionData);
-					updateGroupTransactionData.getSignature());
-			groupRepository.save(groupMemberData);
-		}
 
 		// New owner should be an admin if not already
-		if (!groupRepository.adminExists(groupName, newOwner)) {
+		if (!this.adminExists(newOwner))
-			GroupAdminData groupAdminData = new GroupAdminData(groupName, newOwner, updateGroupTransactionData.getSignature());
+			this.addAdmin(newOwner, updateGroupTransactionData);
-			groupRepository.save(groupAdminData);
-		}
 
 		// Previous owner retained as admin and member
 	}
 
 	public void unupdateGroup(UpdateGroupTransactionData updateGroupTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = updateGroupTransactionData.getGroupName();
-
 		// Previous group reference is taken from this transaction's cached copy
 		this.groupData.setReference(updateGroupTransactionData.getGroupReference());
 
@@ -159,21 +283,23 @@ public class Group {
 
 		// If ownership changed we need to do more work. Note groupData's owner is reverted at this point.
 		String newOwner = updateGroupTransactionData.getNewOwner();
+
 		if (!this.groupData.getOwner().equals(newOwner)) {
 			// If this update caused [what was] new owner to become admin, then revoke that now.
 			// (It's possible they were an admin prior to being given ownership so we need to retain that).
-			GroupAdminData groupAdminData = groupRepository.getAdmin(groupName, newOwner);
+			GroupAdminData groupAdminData = this.getAdmin(newOwner);
-			if (Arrays.equals(groupAdminData.getGroupReference(), updateGroupTransactionData.getSignature()))
+			if (Arrays.equals(groupAdminData.getReference(), updateGroupTransactionData.getSignature()))
-				groupRepository.deleteAdmin(groupName, newOwner);
+				this.deleteAdmin(newOwner);
 
 			// If this update caused [what was] new owner to become member, then revoke that now.
 			// (It's possible they were a member prior to being given ownership so we need to retain that).
-			GroupMemberData groupMemberData = groupRepository.getMember(groupName, newOwner);
+			GroupMemberData groupMemberData = this.getMember(newOwner);
-			if (Arrays.equals(groupMemberData.getGroupReference(), updateGroupTransactionData.getSignature()))
+			if (Arrays.equals(groupMemberData.getReference(), updateGroupTransactionData.getSignature()))
-				groupRepository.deleteMember(groupName, newOwner);
+				this.deleteMember(newOwner);
 		}
 	}
 
+	/** Reverts groupData using previous values stored in referenced transaction. */
 	private void revertGroupUpdate() throws DataException {
 		TransactionData previousTransactionData = this.repository.getTransactionRepository().fromSignature(this.groupData.getReference());
 		if (previousTransactionData == null)
@@ -204,47 +330,46 @@ public class Group {
 	}
 
 	public void promoteToAdmin(AddGroupAdminTransactionData addGroupAdminTransactionData) throws DataException {
-		GroupAdminData groupAdminData = new GroupAdminData(addGroupAdminTransactionData.getGroupName(), addGroupAdminTransactionData.getMember(),
+		this.addAdmin(addGroupAdminTransactionData.getMember(), addGroupAdminTransactionData.getSignature());
-				addGroupAdminTransactionData.getSignature());
-		this.repository.getGroupRepository().save(groupAdminData);
 	}
 
 	public void unpromoteToAdmin(AddGroupAdminTransactionData addGroupAdminTransactionData) throws DataException {
-		this.repository.getGroupRepository().deleteAdmin(addGroupAdminTransactionData.getGroupName(), addGroupAdminTransactionData.getMember());
+		this.deleteAdmin(addGroupAdminTransactionData.getMember());
 	}
 
 	public void demoteFromAdmin(RemoveGroupAdminTransactionData removeGroupAdminTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = removeGroupAdminTransactionData.getGroupName();
 		String admin = removeGroupAdminTransactionData.getAdmin();
 
-		// Save admin's promotion transaction reference for orphaning purposes
+		// Save reference to the transaction that caused adminship so we can revert if orphaning.
-		GroupAdminData groupAdminData = groupRepository.getAdmin(groupName, admin);
+		GroupAdminData groupAdminData = this.getAdmin(admin);
-		removeGroupAdminTransactionData.setGroupReference(groupAdminData.getGroupReference());
+		// Reference now part of this transaction but actually saved into repository by caller.
+		removeGroupAdminTransactionData.setAdminReference(groupAdminData.getReference());
 
 		// Demote
-		groupRepository.deleteAdmin(groupName, admin);
+		this.deleteAdmin(admin);
 	}
 
 	public void undemoteFromAdmin(RemoveGroupAdminTransactionData removeGroupAdminTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = removeGroupAdminTransactionData.getGroupName();
 		String admin = removeGroupAdminTransactionData.getAdmin();
 
-		// Rebuild admin entry using stored promotion transaction reference
+		// Rebuild admin entry using stored reference to transaction that causes adminship
-		GroupAdminData groupAdminData = new GroupAdminData(groupName, admin, removeGroupAdminTransactionData.getGroupReference());
+		this.rebuildAdmin(admin, removeGroupAdminTransactionData.getAdminReference());
-		groupRepository.save(groupAdminData);
+
+		// Clean cached reference in this transaction
+		removeGroupAdminTransactionData.setAdminReference(null);
 	}
 
 	public void kick(GroupKickTransactionData groupKickTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupKickTransactionData.getGroupName();
 		String member = groupKickTransactionData.getMember();
 
-		// If pending join request then this is a essentially a deny response so delete join request and exit
+		// If there is a pending join request then this is a essentially a deny response so delete join request and exit
-		if (groupRepository.joinRequestExists(groupName, member)) {
+		GroupJoinRequestData groupJoinRequestData = this.getJoinRequest(member);
+		if (groupJoinRequestData != null) {
+			// Save reference to the transaction that created join request so we can rebuild join request during orphaning.
+			groupKickTransactionData.setJoinReference(groupJoinRequestData.getReference());
+
 			// Delete join request
-			groupRepository.deleteJoinRequest(groupName, member);
+			this.deleteJoinRequest(member);
 
 			// Make sure kick transaction's member/admin-references are null to indicate that there
 			// was no existing member but actually only a join request. This should prevent orphaning code
@@ -253,271 +378,298 @@ public class Group {
 			groupKickTransactionData.setAdminReference(null);
 
 			return;
+		} else {
+			// Clear any cached join reference
+			groupKickTransactionData.setJoinReference(null);
 		}
 
-		// Store membership and (optionally) adminship transactions for orphaning purposes
+		GroupAdminData groupAdminData = this.getAdmin(member);
-		GroupAdminData groupAdminData = groupRepository.getAdmin(groupName, member);
 		if (groupAdminData != null) {
-			groupKickTransactionData.setAdminReference(groupAdminData.getGroupReference());
+			// Save reference to the transaction that caused adminship so we can rebuild adminship during orphaning.
+			groupKickTransactionData.setAdminReference(groupAdminData.getReference());
 
-			groupRepository.deleteAdmin(groupName, member);
+			// Kicked, so no longer an admin
+			this.deleteAdmin(member);
 		} else {
-			// Not an admin
+			// Not an admin so no reference
 			groupKickTransactionData.setAdminReference(null);
 		}
 
-		GroupMemberData groupMemberData = groupRepository.getMember(groupName, member);
+		GroupMemberData groupMemberData = this.getMember(member);
-		groupKickTransactionData.setMemberReference(groupMemberData.getGroupReference());
+		// Save reference to the transaction that caused membership so we can rebuild membership during orphaning.
+		groupKickTransactionData.setMemberReference(groupMemberData.getReference());
 
-		groupRepository.deleteMember(groupName, member);
+		// Kicked, so no longer a member
+		this.deleteMember(member);
 	}
 
 	public void unkick(GroupKickTransactionData groupKickTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupKickTransactionData.getGroupName();
 		String member = groupKickTransactionData.getMember();
 
-		// If there's no member-reference then there wasn't an actual member, only a join request
+		// If there's no cached reference to the transaction that caused membership then the kick was only a deny response to a join-request.
-		if (groupKickTransactionData.getMemberReference() == null) {
+		byte[] joinReference = groupKickTransactionData.getJoinReference();
+		if (joinReference != null) {
 			// Rebuild join-request
-			GroupJoinRequestData groupJoinRequestData = new GroupJoinRequestData(groupName, member);
+			this.rebuildJoinRequest(member, joinReference);
-			groupRepository.save(groupJoinRequestData);
 
 			return;
 		}
 
 		// Rebuild member entry using stored transaction reference
-		TransactionData membershipTransactionData = this.repository.getTransactionRepository().fromSignature(groupKickTransactionData.getMemberReference());
+		this.rebuildMember(member, groupKickTransactionData.getMemberReference());
-		GroupMemberData groupMemberData = new GroupMemberData(groupName, member, membershipTransactionData.getTimestamp(),
-				membershipTransactionData.getSignature());
-		groupRepository.save(groupMemberData);
 
-		if (groupKickTransactionData.getAdminReference() != null) {
+		if (groupKickTransactionData.getAdminReference() != null)
 			// Rebuild admin entry using stored transaction reference
-			GroupAdminData groupAdminData = new GroupAdminData(groupName, member, groupKickTransactionData.getAdminReference());
+			this.rebuildAdmin(member, groupKickTransactionData.getAdminReference());
-			groupRepository.save(groupAdminData);
+
-		}
+		// Clean cached references to transactions used to rebuild member/admin info
+		groupKickTransactionData.setMemberReference(null);
+		groupKickTransactionData.setAdminReference(null);
 	}
 
 	public void ban(GroupBanTransactionData groupBanTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupBanTransactionData.getGroupName();
 		String offender = groupBanTransactionData.getOffender();
 
 		// Kick if member
-		if (groupRepository.memberExists(groupName, offender)) {
+		if (this.memberExists(offender)) {
-			// Store membership and (optionally) adminship transactions for orphaning purposes
+			GroupAdminData groupAdminData = this.getAdmin(offender);
-			GroupAdminData groupAdminData = groupRepository.getAdmin(groupName, offender);
 			if (groupAdminData != null) {
-				groupBanTransactionData.setAdminReference(groupAdminData.getGroupReference());
+				// Save reference to the transaction that caused adminship so we can revert if orphaning.
+				groupBanTransactionData.setAdminReference(groupAdminData.getReference());
 
-				groupRepository.deleteAdmin(groupName, offender);
+				// Kicked, so no longer an admin
+				this.deleteAdmin(offender);
 			} else {
-				// Not an admin
+				// Not an admin so no reference
 				groupBanTransactionData.setAdminReference(null);
 			}
 
-			GroupMemberData groupMemberData = groupRepository.getMember(groupName, offender);
+			GroupMemberData groupMemberData = this.getMember(offender);
-			groupBanTransactionData.setMemberReference(groupMemberData.getGroupReference());
+			// Save reference to the transaction that caused membership so we can revert if orphaning.
+			groupBanTransactionData.setMemberReference(groupMemberData.getReference());
 
-			groupRepository.deleteMember(groupName, offender);
+			// Kicked, so no longer a member
+			this.deleteMember(offender);
 		} else {
-			groupBanTransactionData.setMemberReference(null);
+			// If there is a pending join request then this is a essentially a deny response so delete join request
+			GroupJoinRequestData groupJoinRequestData = this.getJoinRequest(offender);
+			if (groupJoinRequestData != null) {
+				// Save reference to join request so we can rebuild join request if orphaning,
+				// and differentiate between needing to rebuild join request and rebuild invite.
+				groupBanTransactionData.setJoinInviteReference(groupJoinRequestData.getReference());
 
-			// XXX maybe set join-request reference here?
+				// Delete join request
-			// XXX what about invites?
+				this.deleteJoinRequest(offender);
-		}
 
-		// XXX Delete pending join request
+				// Make sure kick transaction's member/admin-references are null to indicate that there
-		// XXX Delete pending invites
+				// was no existing member but actually only a join request. This should prevent orphaning code
+				// from trying to incorrectly recreate a member/admin.
+				groupBanTransactionData.setMemberReference(null);
+				groupBanTransactionData.setAdminReference(null);
+			} else {
+				// No join request, but there could be a pending invite
+				GroupInviteData groupInviteData = this.getInvite(offender);
+				if (groupInviteData != null) {
+					// Save reference to invite so we can rebuild invite if orphaning,
+					// and differentiate between needing to rebuild join request and rebuild invite.
+					groupBanTransactionData.setJoinInviteReference(groupInviteData.getReference());
 
-		// Ban
+					// Delete invite
-		Account admin = new PublicKeyAccount(this.repository, groupBanTransactionData.getAdminPublicKey());
+					this.deleteInvite(offender);
-		long banned = groupBanTransactionData.getTimestamp();
-		String reason = groupBanTransactionData.getReason();
 
-		Long expiry = null;
+					// Make sure kick transaction's member/admin-references are null to indicate that there
-		int timeToLive = groupBanTransactionData.getTimeToLive();
+					// was no existing member but actually only a join request. This should prevent orphaning code
-		if (timeToLive != 0)
+					// from trying to incorrectly recreate a member/admin.
-			expiry = groupBanTransactionData.getTimestamp() + timeToLive * 1000;
+					groupBanTransactionData.setMemberReference(null);
-
+					groupBanTransactionData.setAdminReference(null);
-		// Save reference to banning transaction for orphaning purposes
+				}
-		byte[] reference = groupBanTransactionData.getSignature();
-
-		GroupBanData groupBanData = new GroupBanData(groupName, offender, admin.getAddress(), banned, reason, expiry, reference);
-		groupRepository.save(groupBanData);
-	}
-
-	public void unban(GroupBanTransactionData groupBanTransactionData) throws DataException {
-		// Orphaning version of "ban" - not actual "unban"
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupBanTransactionData.getGroupName();
-		String offender = groupBanTransactionData.getOffender();
-
-		// If was kicked as part of ban then reinstate
-		if (groupBanTransactionData.getMemberReference() != null) {
-			// Rebuild member entry using stored transaction reference
-			TransactionData membershipTransactionData = this.repository.getTransactionRepository().fromSignature(groupBanTransactionData.getMemberReference());
-			GroupMemberData groupMemberData = new GroupMemberData(groupName, offender, membershipTransactionData.getTimestamp(),
-					membershipTransactionData.getSignature());
-			groupRepository.save(groupMemberData);
-
-			if (groupBanTransactionData.getAdminReference() != null) {
-				// Rebuild admin entry using stored transaction reference
-				GroupAdminData groupAdminData = new GroupAdminData(groupName, offender, groupBanTransactionData.getAdminReference());
-				groupRepository.save(groupAdminData);
 			}
 		}
 
-		// XXX Reinstate pending join request
+		// Create ban
-		// XXX Reinstate pending invites
+		this.addBan(groupBanTransactionData);
-
-		// Delete ban
-		groupRepository.deleteBan(groupName, offender);
 	}
 
-	public void cancelBan(GroupUnbanTransactionData groupUnbanTransactionData) throws DataException {
+	public void unban(GroupBanTransactionData groupBanTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
+		// Orphaning version of "ban" - not "cancel-ban"!
-		String groupName = groupUnbanTransactionData.getGroupName();
+		String offender = groupBanTransactionData.getOffender();
+
+		// Delete ban
+		groupRepository.deleteBan(this.groupData.getGroupId(), offender);
+
+		// If member was kicked as part of ban then reinstate
+		if (groupBanTransactionData.getMemberReference() != null) {
+			this.rebuildMember(offender, groupBanTransactionData.getMemberReference());
+
+			if (groupBanTransactionData.getAdminReference() != null)
+				// Rebuild admin entry using stored transaction reference
+				this.rebuildAdmin(offender, groupBanTransactionData.getAdminReference());
+		} else {
+			// Do we need to reinstate pending invite or join-request?
+			byte[] groupReference = groupBanTransactionData.getJoinInviteReference();
+			if (groupReference != null) {
+				TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(groupReference);
+
+				switch (transactionData.getType()) {
+					case GROUP_INVITE:
+						// Reinstate invite
+						this.rebuildInvite(offender, groupReference);
+						break;
+
+					case JOIN_GROUP:
+						// Rebuild join-request
+						this.rebuildJoinRequest(offender, groupReference);
+						break;
+
+					default:
+						throw new IllegalStateException("Unable to revert group transaction due to unsupported referenced transaction");
+				}
+			}
+		}
+	}
+
+	public void cancelBan(CancelGroupBanTransactionData groupUnbanTransactionData) throws DataException {
 		String member = groupUnbanTransactionData.getMember();
 
-		GroupBanData groupBanData = groupRepository.getBan(groupName, member);
+		GroupBanData groupBanData = groupRepository.getBan(this.groupData.getGroupId(), member);
 
 		// Save reference to banning transaction for orphaning purposes
-		groupUnbanTransactionData.setGroupReference(groupBanData.getReference());
+		groupUnbanTransactionData.setBanReference(groupBanData.getReference());
 
 		// Delete ban
-		groupRepository.deleteBan(groupName, member);
+		groupRepository.deleteBan(this.groupData.getGroupId(), member);
 	}
 
-	public void uncancelBan(GroupUnbanTransactionData groupUnbanTransactionData) throws DataException {
+	public void uncancelBan(CancelGroupBanTransactionData groupUnbanTransactionData) throws DataException {
-		// Reinstate ban
+		// Reinstate ban using cached reference to banning transaction, stored in our transaction
-		TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(groupUnbanTransactionData.getGroupReference());
+		TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(groupUnbanTransactionData.getBanReference());
-		ban((GroupBanTransactionData) transactionData);
+		this.addBan((GroupBanTransactionData) transactionData);
 
-		groupUnbanTransactionData.setGroupReference(null);
+		// Clear cached reference to banning transaction
+		groupUnbanTransactionData.setBanReference(null);
 	}
 
 	public void invite(GroupInviteTransactionData groupInviteTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
+		String invitee = groupInviteTransactionData.getInvitee();
-		String groupName = groupInviteTransactionData.getGroupName();
-		Account inviter = new PublicKeyAccount(this.repository, groupInviteTransactionData.getAdminPublicKey());
 
 		// If there is a pending "join request" then add new group member
-		if (groupRepository.joinRequestExists(groupName, groupInviteTransactionData.getInvitee())) {
+		GroupJoinRequestData groupJoinRequestData = this.getJoinRequest(invitee);
-			GroupMemberData groupMemberData = new GroupMemberData(groupName, groupInviteTransactionData.getInvitee(), groupInviteTransactionData.getTimestamp(),
+		if (groupJoinRequestData != null) {
-					groupInviteTransactionData.getSignature());
+			this.addMember(invitee, groupInviteTransactionData);
-			groupRepository.save(groupMemberData);
+
+			// Save reference to transaction that created join request so we can rebuild join request during orphaning.
+			groupInviteTransactionData.setJoinReference(groupJoinRequestData.getReference());
 
 			// Delete join request
-			groupRepository.deleteJoinRequest(groupName, groupInviteTransactionData.getInvitee());
+			this.deleteJoinRequest(invitee);
 
 			return;
 		}
 
-		Long expiry = null;
+		this.addInvite(groupInviteTransactionData);
-		int timeToLive = groupInviteTransactionData.getTimeToLive();
-		if (timeToLive != 0)
-			expiry = groupInviteTransactionData.getTimestamp() + timeToLive * 1000;
-
-		GroupInviteData groupInviteData = new GroupInviteData(groupName, inviter.getAddress(), groupInviteTransactionData.getInvitee(), expiry,
-				groupInviteTransactionData.getSignature());
-		groupRepository.save(groupInviteData);
 	}
 
 	public void uninvite(GroupInviteTransactionData groupInviteTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupInviteTransactionData.getGroupName();
-		Account inviter = new PublicKeyAccount(this.repository, groupInviteTransactionData.getAdminPublicKey());
 		String invitee = groupInviteTransactionData.getInvitee();
 
-		// Put back any "join request"
+		// If member exists then they were added when invite matched join request
-		if (groupRepository.memberExists(groupName, invitee)) {
+		if (this.memberExists(invitee)) {
-			GroupJoinRequestData groupJoinRequestData = new GroupJoinRequestData(groupName, invitee);
+			// Rebuild join request using cached reference to transaction that created join request.
-			groupRepository.save(groupJoinRequestData);
+			this.rebuildJoinRequest(invitee, groupInviteTransactionData.getJoinReference());
 
 			// Delete member
-			groupRepository.deleteMember(groupName, invitee);
+			this.deleteMember(invitee);
+
+			// Clear cached reference
+			groupInviteTransactionData.setJoinReference(null);
 		}
 
 		// Delete invite
-		groupRepository.deleteInvite(groupName, inviter.getAddress(), invitee);
+		this.deleteInvite(invitee);
 	}
 
 	public void cancelInvite(CancelGroupInviteTransactionData cancelGroupInviteTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = cancelGroupInviteTransactionData.getGroupName();
-		Account inviter = new PublicKeyAccount(this.repository, cancelGroupInviteTransactionData.getAdminPublicKey());
 		String invitee = cancelGroupInviteTransactionData.getInvitee();
 
-		// Save invite's transaction signature for orphaning purposes
+		// Save reference to invite transaction so invite can be rebuilt during orphaning.
-		GroupInviteData groupInviteData = groupRepository.getInvite(groupName, inviter.getAddress(), invitee);
+		GroupInviteData groupInviteData = this.getInvite(invitee);
-		cancelGroupInviteTransactionData.setGroupReference(groupInviteData.getReference());
+		cancelGroupInviteTransactionData.setInviteReference(groupInviteData.getReference());
 
 		// Delete invite
-		groupRepository.deleteInvite(groupName, inviter.getAddress(), invitee);
+		this.deleteInvite(invitee);
 	}
 
 	public void uncancelInvite(CancelGroupInviteTransactionData cancelGroupInviteTransactionData) throws DataException {
 		// Reinstate invite
-		TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(cancelGroupInviteTransactionData.getGroupReference());
+		TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(cancelGroupInviteTransactionData.getInviteReference());
-		invite((GroupInviteTransactionData) transactionData);
+		this.addInvite((GroupInviteTransactionData) transactionData);
 
-		cancelGroupInviteTransactionData.setGroupReference(null);
+		// Clear cached reference to invite transaction
+		cancelGroupInviteTransactionData.setInviteReference(null);
 	}
 
 	public void join(JoinGroupTransactionData joinGroupTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = joinGroupTransactionData.getGroupName();
 		Account joiner = new PublicKeyAccount(this.repository, joinGroupTransactionData.getJoinerPublicKey());
 
-		// Set invite transactions' group-reference to this transaction's signature so the invites can be put back if we orphan this join
+		// Any pending invite?
-		// Delete any pending invites
+		GroupInviteData groupInviteData = this.getInvite(joiner.getAddress());
-		List<GroupInviteData> invites = groupRepository.getInvitesByInvitee(groupName, joiner.getAddress());
-		for (GroupInviteData invite : invites) {
-			TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(invite.getReference());
-			((GroupInviteTransactionData) transactionData).setGroupReference(joinGroupTransactionData.getSignature());
 
-			groupRepository.deleteInvite(groupName, invite.getInviter(), joiner.getAddress());
+		// If there is no invites and this group is "closed" (i.e. invite-only) then
-		}
-
-		// If there were no invites and this group is "closed" (i.e. invite-only) then
 		// this is now a pending "join request"
-		if (invites.isEmpty() && !groupData.getIsOpen()) {
+		if (groupInviteData == null && !groupData.getIsOpen()) {
-			GroupJoinRequestData groupJoinRequestData = new GroupJoinRequestData(groupName, joiner.getAddress());
+			// Save join request
-			groupRepository.save(groupJoinRequestData);
+			this.addJoinRequest(joiner.getAddress(), joinGroupTransactionData.getSignature());
+
+			// Clear any reference to invite transaction to prevent invite rebuild during orphaning.
+			joinGroupTransactionData.setInviteReference(null);
+
 			return;
 		}
 
-		// Actually add new member to group
+		// Any invite?
-		GroupMemberData groupMemberData = new GroupMemberData(groupName, joiner.getAddress(), joinGroupTransactionData.getTimestamp(),
+		if (groupInviteData != null) {
-				joinGroupTransactionData.getSignature());
+			// Save reference to invite transaction so invite can be rebuilt during orphaning.
-		groupRepository.save(groupMemberData);
+			joinGroupTransactionData.setInviteReference(groupInviteData.getReference());
 
+			// Delete invite
+			this.deleteInvite(joiner.getAddress());
+		} else {
+			// Clear any reference to invite transaction to prevent invite rebuild during orphaning.
+			joinGroupTransactionData.setInviteReference(null);
+		}
+
+		// Actually add new member to group
+		this.addMember(joiner.getAddress(), joinGroupTransactionData);
 	}
 
 	public void unjoin(JoinGroupTransactionData joinGroupTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = joinGroupTransactionData.getGroupName();
 		Account joiner = new PublicKeyAccount(this.repository, joinGroupTransactionData.getJoinerPublicKey());
 
-		groupRepository.deleteMember(groupName, joiner.getAddress());
+		byte[] inviteReference = joinGroupTransactionData.getInviteReference();
 
-		// Put back any pending invites
+		// Was this a join-request only?
-		List<GroupInviteTransactionData> inviteTransactions = this.repository.getTransactionRepository()
+		if (inviteReference == null && !groupData.getIsOpen()) {
-				.getInvitesWithGroupReference(joinGroupTransactionData.getSignature());
+			// Delete join request
-		for (GroupInviteTransactionData inviteTransaction : inviteTransactions) {
+			this.deleteJoinRequest(joiner.getAddress());
-			this.invite(inviteTransaction);
 
-			// Remove group-reference
+			return;
-			inviteTransaction.setGroupReference(null);
-			this.repository.getTransactionRepository().save(inviteTransaction);
 		}
+
+		// Any invite to rebuild?
+		if (inviteReference != null) {
+			// Rebuild invite using cache reference to invite transaction
+			TransactionData transactionData = this.repository.getTransactionRepository().fromSignature(inviteReference);
+			this.addInvite((GroupInviteTransactionData) transactionData);
+
+			// Clear cached reference to invite transaction
+			joinGroupTransactionData.setInviteReference(null);
+		}
+
+		// Delete member
+		this.deleteMember(joiner.getAddress());
 	}
 
 	public void leave(LeaveGroupTransactionData leaveGroupTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = leaveGroupTransactionData.getGroupName();
 		Account leaver = new PublicKeyAccount(this.repository, leaveGroupTransactionData.getLeaverPublicKey());
 
 		// Potentially record reference to transaction that restores previous admin state.
@@ -526,41 +678,35 @@ public class Group {
 		// Owners are also admins, so skip if owner
 		if (!leaver.getAddress().equals(this.groupData.getOwner())) {
 			// Fetch admin data for leaver
-			GroupAdminData groupAdminData = groupRepository.getAdmin(groupName, leaver.getAddress());
+			GroupAdminData groupAdminData = this.getAdmin(leaver.getAddress());
 
 			if (groupAdminData != null) {
-				// Leaver is admin - use promotion transaction reference as restore-state reference
+				// Save reference to transaction that caused adminship in our transaction so we can rebuild adminship during orphaning.
-				leaveGroupTransactionData.setAdminReference(groupAdminData.getGroupReference());
+				leaveGroupTransactionData.setAdminReference(groupAdminData.getReference());
 
 				// Remove as admin
-				groupRepository.deleteAdmin(groupName, leaver.getAddress());
+				this.deleteAdmin(leaver.getAddress());
 			}
 		}
 
-		// Save membership transaction reference
+		// Save reference to transaction that caused membership in our transaction so we can rebuild membership during orphaning.
-		GroupMemberData groupMemberData = groupRepository.getMember(groupName, leaver.getAddress());
+		GroupMemberData groupMemberData = this.getMember(leaver.getAddress());
-		leaveGroupTransactionData.setMemberReference(groupMemberData.getGroupReference());
+		leaveGroupTransactionData.setMemberReference(groupMemberData.getReference());
 
 		// Remove as member
-		groupRepository.deleteMember(leaveGroupTransactionData.getGroupName(), leaver.getAddress());
+		this.deleteMember(leaver.getAddress());
 	}
 
 	public void unleave(LeaveGroupTransactionData leaveGroupTransactionData) throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = leaveGroupTransactionData.getGroupName();
 		Account leaver = new PublicKeyAccount(this.repository, leaveGroupTransactionData.getLeaverPublicKey());
 
-		// Rejoin as member
+		// Restore membership using cached reference to transaction that caused membership
-		TransactionData membershipTransactionData = this.repository.getTransactionRepository().fromSignature(leaveGroupTransactionData.getMemberReference());
+		this.rebuildMember(leaver.getAddress(), leaveGroupTransactionData.getMemberReference());
-		groupRepository
-				.save(new GroupMemberData(groupName, leaver.getAddress(), membershipTransactionData.getTimestamp(), membershipTransactionData.getSignature()));
 
-		// Put back any admin state based on referenced group-related transaction
 		byte[] adminTransactionSignature = leaveGroupTransactionData.getAdminReference();
-		if (adminTransactionSignature != null) {
+		if (adminTransactionSignature != null)
-			GroupAdminData groupAdminData = new GroupAdminData(leaveGroupTransactionData.getGroupName(), leaver.getAddress(), adminTransactionSignature);
+			// Restore adminship using cached reference to transaction that caused adminship
-			groupRepository.save(groupAdminData);
+			this.rebuildAdmin(leaver.getAddress(), adminTransactionSignature);
-		}
 	}
 
 }

src/main/java/org/qora/repository/GroupRepository.java

@@ -13,81 +13,89 @@ public interface GroupRepository {
 
 	// Groups
 
+	public GroupData fromGroupId(int groupId) throws DataException;
+
 	public GroupData fromGroupName(String groupName) throws DataException;
 
+	public boolean groupExists(int groupId) throws DataException;
+
 	public boolean groupExists(String groupName) throws DataException;
 
 	public List<GroupData> getAllGroups() throws DataException;
 
 	public List<GroupData> getGroupsByOwner(String address) throws DataException;
 
+	public List<GroupData> getGroupsWithMember(String member) throws DataException;
+
 	public void save(GroupData groupData) throws DataException;
 
+	public void delete(int groupId) throws DataException;
+
 	public void delete(String groupName) throws DataException;
 
 	// Group Admins
 
-	public GroupAdminData getAdmin(String groupName, String address) throws DataException;
+	public GroupAdminData getAdmin(int groupId, String address) throws DataException;
 
-	public boolean adminExists(String groupName, String address) throws DataException;
+	public boolean adminExists(int groupId, String address) throws DataException;
 
-	public List<GroupAdminData> getGroupAdmins(String groupName) throws DataException;
+	public List<GroupAdminData> getGroupAdmins(int groupId) throws DataException;
 
 	public void save(GroupAdminData groupAdminData) throws DataException;
 
-	public void deleteAdmin(String groupName, String address) throws DataException;
+	public void deleteAdmin(int groupId, String address) throws DataException;
 
 	// Group Members
 
-	public GroupMemberData getMember(String groupName, String address) throws DataException;
+	public GroupMemberData getMember(int groupId, String address) throws DataException;
 
-	public boolean memberExists(String groupName, String address) throws DataException;
+	public boolean memberExists(int groupId, String address) throws DataException;
 
-	public List<GroupMemberData> getGroupMembers(String groupName) throws DataException;
+	public List<GroupMemberData> getGroupMembers(int groupId) throws DataException;
 
 	/** Returns number of group members, or null if group doesn't exist */
-	public Integer countGroupMembers(String groupName) throws DataException;
+	public Integer countGroupMembers(int groupId) throws DataException;
 
 	public void save(GroupMemberData groupMemberData) throws DataException;
 
-	public void deleteMember(String groupName, String address) throws DataException;
+	public void deleteMember(int groupId, String address) throws DataException;
 
 	// Group Invites
 
-	public GroupInviteData getInvite(String groupName, String inviter, String invitee) throws DataException;
+	public GroupInviteData getInvite(int groupId, String invitee) throws DataException;
 
-	public boolean inviteExists(String groupName, String invitee) throws DataException;
+	public boolean inviteExists(int groupId, String invitee) throws DataException;
 
-	public boolean inviteExists(String groupName, String inviter, String invitee) throws DataException;
+	public List<GroupInviteData> getGroupInvites(int groupId) throws DataException;
 
-	public List<GroupInviteData> getGroupInvites(String groupName) throws DataException;
+	public List<GroupInviteData> getInvitesByInvitee(String invitee) throws DataException;
-
-	public List<GroupInviteData> getInvitesByInvitee(String groupName, String invitee) throws DataException;
 
 	public void save(GroupInviteData groupInviteData) throws DataException;
 
-	public void deleteInvite(String groupName, String inviter, String invitee) throws DataException;
+	public void deleteInvite(int groupId, String invitee) throws DataException;
 
 	// Group Join Requests
 
-	public boolean joinRequestExists(String groupName, String joiner) throws DataException;
+	public GroupJoinRequestData getJoinRequest(Integer groupId, String joiner) throws DataException;
 
-	public List<GroupJoinRequestData> getGroupJoinRequests(String groupName) throws DataException;
+	public boolean joinRequestExists(int groupId, String joiner) throws DataException;
+
+	public List<GroupJoinRequestData> getGroupJoinRequests(int groupId) throws DataException;
 
 	public void save(GroupJoinRequestData groupJoinRequestData) throws DataException;
 
-	public void deleteJoinRequest(String groupName, String joiner) throws DataException;
+	public void deleteJoinRequest(int groupId, String joiner) throws DataException;
 
 	// Group Bans
 
-	public GroupBanData getBan(String groupName, String member) throws DataException;
+	public GroupBanData getBan(int groupId, String member) throws DataException;
 
-	public boolean banExists(String groupName, String offender) throws DataException;
+	public boolean banExists(int groupId, String offender) throws DataException;
 
-	public List<GroupBanData> getGroupBans(String groupName) throws DataException;
+	public List<GroupBanData> getGroupBans(int groupId) throws DataException;
 
 	public void save(GroupBanData groupBanData) throws DataException;
 
-	public void deleteBan(String groupName, String offender) throws DataException;
+	public void deleteBan(int groupId, String offender) throws DataException;
 
 }

src/main/java/org/qora/repository/TransactionRepository.java

@@ -2,7 +2,6 @@ package org.qora.repository;
 
 import java.util.List;
 
-import org.qora.data.transaction.GroupInviteTransactionData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.transaction.Transaction.TransactionType;
 
@@ -53,8 +52,4 @@ public interface TransactionRepository {
 
 	public void delete(TransactionData transactionData) throws DataException;
 
-	/** Returns transaction data for group invite transactions that have groupReference that matches passed value.
-	 * @throws DataException */
-	public List<GroupInviteTransactionData> getInvitesWithGroupReference(byte[] groupReference) throws DataException;
-
 }

src/main/java/org/qora/repository/hsqldb/HSQLDBDatabaseUpdates.java

@@ -91,22 +91,27 @@ public class HSQLDBDatabaseUpdates {
 					stmt.execute("CREATE TYPE QoraPublicKey AS VARBINARY(32)");
 					stmt.execute("CREATE TYPE QoraAmount AS DECIMAL(27, 8)");
 					stmt.execute("CREATE TYPE GenericDescription AS VARCHAR(4000)");
-					stmt.execute("CREATE TYPE RegisteredName AS VARCHAR(400) COLLATE SQL_TEXT_NO_PAD");
+					stmt.execute("CREATE TYPE RegisteredName AS VARCHAR(128) COLLATE SQL_TEXT_NO_PAD");
 					stmt.execute("CREATE TYPE NameData AS VARCHAR(4000)");
-					stmt.execute("CREATE TYPE PollName AS VARCHAR(400) COLLATE SQL_TEXT_NO_PAD");
+					stmt.execute("CREATE TYPE MessageData AS VARBINARY(4000)");
-					stmt.execute("CREATE TYPE PollOption AS VARCHAR(400) COLLATE SQL_TEXT_UCC_NO_PAD");
+					stmt.execute("CREATE TYPE PollName AS VARCHAR(128) COLLATE SQL_TEXT_NO_PAD");
+					stmt.execute("CREATE TYPE PollOption AS VARCHAR(80) COLLATE SQL_TEXT_UCC_NO_PAD");
 					stmt.execute("CREATE TYPE PollOptionIndex AS INTEGER");
 					stmt.execute("CREATE TYPE DataHash AS VARBINARY(32)");
 					stmt.execute("CREATE TYPE AssetID AS BIGINT");
-					stmt.execute("CREATE TYPE AssetName AS VARCHAR(400) COLLATE SQL_TEXT_NO_PAD");
+					stmt.execute("CREATE TYPE AssetName AS VARCHAR(34) COLLATE SQL_TEXT_NO_PAD");
 					stmt.execute("CREATE TYPE AssetOrderID AS VARBINARY(64)");
-					stmt.execute("CREATE TYPE ATName AS VARCHAR(200) COLLATE SQL_TEXT_UCC_NO_PAD");
+					stmt.execute("CREATE TYPE ATName AS VARCHAR(32) COLLATE SQL_TEXT_UCC_NO_PAD");
-					stmt.execute("CREATE TYPE ATType AS VARCHAR(200) COLLATE SQL_TEXT_UCC_NO_PAD");
+					stmt.execute("CREATE TYPE ATType AS VARCHAR(32) COLLATE SQL_TEXT_UCC_NO_PAD");
+					stmt.execute("CREATE TYPE ATTags AS VARCHAR(32) COLLATE SQL_TEXT_UCC_NO_PAD");
 					stmt.execute("CREATE TYPE ATCode AS BLOB(64K)"); // 16bit * 1
 					stmt.execute("CREATE TYPE ATState AS BLOB(1M)"); // 16bit * 8 + 16bit * 4 + 16bit * 4
+					stmt.execute("CREATE TYPE ATCreationBytes AS BLOB(576K)"); // 16bit * 1 + 16bit * 8
 					stmt.execute("CREATE TYPE ATStateHash as VARBINARY(32)");
 					stmt.execute("CREATE TYPE ATMessage AS VARBINARY(256)");
+					stmt.execute("CREATE TYPE GroupID AS INTEGER");
 					stmt.execute("CREATE TYPE GroupName AS VARCHAR(400) COLLATE SQL_TEXT_UCC_NO_PAD");
+					stmt.execute("CREATE TYPE GroupReason AS VARCHAR(128) COLLATE SQL_TEXT_UCC_NO_PAD");
 					break;
 
 				case 1:
@@ -283,8 +288,8 @@ public class HSQLDBDatabaseUpdates {
 				case 19:
 					// Deploy CIYAM AT Transactions
 					stmt.execute("CREATE TABLE DeployATTransactions (signature Signature, creator QoraPublicKey NOT NULL, AT_name ATName NOT NULL, "
-							+ "description VARCHAR(2000) NOT NULL, AT_type ATType NOT NULL, AT_tags VARCHAR(200) NOT NULL, "
+							+ "description GenericDescription NOT NULL, AT_type ATType NOT NULL, AT_tags ATTags NOT NULL, "
-							+ "creation_bytes VARBINARY(100000) NOT NULL, amount QoraAmount NOT NULL, asset_id AssetID NOT NULL, AT_address QoraAddress, "
+							+ "creation_bytes ATCreationBytes NOT NULL, amount QoraAmount NOT NULL, asset_id AssetID NOT NULL, AT_address QoraAddress, "
 							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 					// For looking up the Deploy AT Transaction based on deployed AT address
 					stmt.execute("CREATE INDEX DeployATAddressIndex on DeployATTransactions (AT_address)");
@@ -294,7 +299,7 @@ public class HSQLDBDatabaseUpdates {
 					// Message Transactions
 					stmt.execute(
 							"CREATE TABLE MessageTransactions (signature Signature, version TINYINT NOT NULL, sender QoraPublicKey NOT NULL, recipient QoraAddress NOT NULL, "
-									+ "is_text BOOLEAN NOT NULL, is_encrypted BOOLEAN NOT NULL, amount QoraAmount NOT NULL, asset_id AssetID NOT NULL, data VARBINARY(4000) NOT NULL, "
+									+ "is_text BOOLEAN NOT NULL, is_encrypted BOOLEAN NOT NULL, amount QoraAmount NOT NULL, asset_id AssetID NOT NULL, data MessageData NOT NULL, "
 									+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 					break;
 
@@ -303,7 +308,7 @@ public class HSQLDBDatabaseUpdates {
 					stmt.execute("CREATE TABLE Assets (asset_id AssetID, owner QoraAddress NOT NULL, "
 							+ "asset_name AssetName NOT NULL, description GenericDescription NOT NULL, "
 							+ "quantity BIGINT NOT NULL, is_divisible BOOLEAN NOT NULL, reference Signature NOT NULL, PRIMARY KEY (asset_id))");
-					// We need a corresponding trigger to make sure new asset_id values are assigned sequentially
+					// We need a corresponding trigger to make sure new asset_id values are assigned sequentially start from 0
 					stmt.execute(
 							"CREATE TRIGGER Asset_ID_Trigger BEFORE INSERT ON Assets REFERENCING NEW ROW AS new_row FOR EACH ROW WHEN (new_row.asset_id IS NULL) "
 									+ "SET new_row.asset_id = (SELECT IFNULL(MAX(asset_id) + 1, 0) FROM Assets)");
@@ -359,10 +364,9 @@ public class HSQLDBDatabaseUpdates {
 
 				case 26:
 					// Registered Names
-					stmt.execute(
+					stmt.execute("CREATE TABLE Names (name RegisteredName, data NameData NOT NULL, owner QoraAddress NOT NULL, "
-							"CREATE TABLE Names (name RegisteredName, data VARCHAR(4000) NOT NULL, owner QoraAddress NOT NULL, "
+							+ "registered TIMESTAMP WITH TIME ZONE NOT NULL, updated TIMESTAMP WITH TIME ZONE, reference Signature, is_for_sale BOOLEAN NOT NULL, sale_price QoraAmount, "
-									+ "registered TIMESTAMP WITH TIME ZONE NOT NULL, updated TIMESTAMP WITH TIME ZONE, reference Signature, is_for_sale BOOLEAN NOT NULL, sale_price QoraAmount, "
+							+ "PRIMARY KEY (name))");
-									+ "PRIMARY KEY (name))");
 					break;
 
 				case 27:
@@ -394,90 +398,106 @@ public class HSQLDBDatabaseUpdates {
 
 				case 28:
 					// Account groups
-					stmt.execute("CREATE TABLE AccountGroups (group_name GroupName, owner QoraAddress NOT NULL, description GenericDescription NOT NULL, "
+					stmt.execute(
-							+ "created TIMESTAMP WITH TIME ZONE NOT NULL, updated TIMESTAMP WITH TIME ZONE, is_open BOOLEAN NOT NULL, "
+							"CREATE TABLE Groups (group_id GroupID, owner QoraAddress NOT NULL, group_name GroupName, description GenericDescription NOT NULL, "
-							+ "reference Signature, PRIMARY KEY (group_name))");
+									+ "created TIMESTAMP WITH TIME ZONE NOT NULL, updated TIMESTAMP WITH TIME ZONE, is_open BOOLEAN NOT NULL, "
+									+ "reference Signature, PRIMARY KEY (group_id))");
+					// We need a corresponding trigger to make sure new group_id values are assigned sequentially starting from 1
+					stmt.execute(
+							"CREATE TRIGGER Group_ID_Trigger BEFORE INSERT ON Groups REFERENCING NEW ROW AS new_row FOR EACH ROW WHEN (new_row.group_id IS NULL) "
+									+ "SET new_row.group_id = (SELECT IFNULL(MAX(group_id) + 1, 1) FROM Groups)");
+					// For when a user wants to lookup an group by name
+					stmt.execute("CREATE INDEX GroupNameIndex on Groups (group_name)");
 					// For finding groups by owner
-					stmt.execute("CREATE INDEX AccountGroupOwnerIndex ON AccountGroups (owner)");
+					stmt.execute("CREATE INDEX GroupOwnerIndex ON Groups (owner)");
 
 					// Admins
-					stmt.execute("CREATE TABLE AccountGroupAdmins (group_name GroupName, admin QoraAddress, group_reference Signature NOT NULL, PRIMARY KEY (group_name, admin))");
+					stmt.execute("CREATE TABLE GroupAdmins (group_id GroupID, admin QoraAddress, reference Signature NOT NULL, "
+							+ "PRIMARY KEY (group_id, admin), FOREIGN KEY (group_id) REFERENCES Groups (group_id) ON DELETE CASCADE)");
 					// For finding groups that address administrates
-					stmt.execute("CREATE INDEX AccountGroupAdminIndex ON AccountGroupAdmins (admin)");
+					stmt.execute("CREATE INDEX GroupAdminIndex ON GroupAdmins (admin)");
 
 					// Members
-					stmt.execute("CREATE TABLE AccountGroupMembers (group_name GroupName, address QoraAddress, joined TIMESTAMP WITH TIME ZONE NOT NULL, group_reference Signature NOT NULL, "
+					stmt.execute(
-							+ "PRIMARY KEY (group_name, address))");
+							"CREATE TABLE GroupMembers (group_id GroupID, address QoraAddress, joined TIMESTAMP WITH TIME ZONE NOT NULL, reference Signature NOT NULL, "
+									+ "PRIMARY KEY (group_id, address), FOREIGN KEY (group_id) REFERENCES Groups (group_id) ON DELETE CASCADE)");
 					// For finding groups that address is member
-					stmt.execute("CREATE INDEX AccountGroupMemberIndex ON AccountGroupMembers (address)");
+					stmt.execute("CREATE INDEX GroupMemberIndex ON GroupMembers (address)");
 
 					// Invites
-					// PRIMARY KEY (invitee + group + inviter) because most queries will be "what have I been invited to?" from UI
+					stmt.execute("CREATE TABLE GroupInvites (group_id GroupID, inviter QoraAddress, invitee QoraAddress, "
-					stmt.execute("CREATE TABLE AccountGroupInvites (group_name GroupName, inviter QoraAddress, invitee QoraAddress, "
+							+ "expiry TIMESTAMP WITH TIME ZONE NOT NULL, reference Signature, "
-							+ "expiry TIMESTAMP WITH TIME ZONE NOT NULL, reference Signature, PRIMARY KEY (invitee, group_name, inviter))");
+							+ "PRIMARY KEY (group_id, invitee), FOREIGN KEY (group_id) REFERENCES Groups (group_id) ON DELETE CASCADE)");
 					// For finding invites sent by inviter
-					stmt.execute("CREATE INDEX AccountGroupSentInviteIndex ON AccountGroupInvites (inviter)");
+					stmt.execute("CREATE INDEX GroupInviteInviterIndex ON GroupInvites (inviter)");
 					// For finding invites by group
-					stmt.execute("CREATE INDEX AccountGroupInviteIndex ON AccountGroupInvites (group_name)");
+					stmt.execute("CREATE INDEX GroupInviteInviteeIndex ON GroupInvites (invitee)");
 					// For expiry maintenance
-					stmt.execute("CREATE INDEX AccountGroupInviteExpiryIndex ON AccountGroupInvites (expiry)");
+					stmt.execute("CREATE INDEX GroupInviteExpiryIndex ON GroupInvites (expiry)");
 
 					// Pending "join requests"
-					stmt.execute("CREATE TABLE AccountGroupJoinRequests (group_name GroupName, joiner QoraAddress, "
+					stmt.execute(
-							+ "PRIMARY KEY (group_name, joiner))");
+							"CREATE TABLE GroupJoinRequests (group_id GroupID, joiner QoraAddress, reference Signature NOT NULL, PRIMARY KEY (group_id, joiner))");
 
 					// Bans
 					// NULL expiry means does not expire!
-					stmt.execute("CREATE TABLE AccountGroupBans (group_name GroupName, offender QoraAddress, admin QoraAddress NOT NULL, banned TIMESTAMP WITH TIME ZONE NOT NULL, "
+					stmt.execute(
-							+ "reason GenericDescription NOT NULL, expiry TIMESTAMP WITH TIME ZONE, reference Signature NOT NULL, "
+							"CREATE TABLE GroupBans (group_id GroupID, offender QoraAddress, admin QoraAddress NOT NULL, banned TIMESTAMP WITH TIME ZONE NOT NULL, "
-							+ "PRIMARY KEY (group_name, offender))");
+									+ "reason GenericDescription NOT NULL, expiry TIMESTAMP WITH TIME ZONE, reference Signature NOT NULL, "
+									+ "PRIMARY KEY (group_id, offender), FOREIGN KEY (group_id) REFERENCES Groups (group_id) ON DELETE CASCADE)");
 					// For expiry maintenance
-					stmt.execute("CREATE INDEX AccountGroupBanExpiryIndex ON AccountGroupBans (expiry)");
+					stmt.execute("CREATE INDEX GroupBanExpiryIndex ON GroupBans (expiry)");
 					break;
 
 				case 29:
 					// Account group transactions
 					stmt.execute("CREATE TABLE CreateGroupTransactions (signature Signature, creator QoraPublicKey NOT NULL, group_name GroupName NOT NULL, "
-							+ "owner QoraAddress NOT NULL, description GenericDescription NOT NULL, is_open BOOLEAN NOT NULL, "
+							+ "owner QoraAddress NOT NULL, description GenericDescription NOT NULL, is_open BOOLEAN NOT NULL, group_id GroupID, "
 							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
-					stmt.execute("CREATE TABLE UpdateGroupTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_name GroupName NOT NULL, "
+					stmt.execute("CREATE TABLE UpdateGroupTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_id GroupID NOT NULL, "
 							+ "new_owner QoraAddress NOT NULL, new_description GenericDescription NOT NULL, new_is_open BOOLEAN NOT NULL, group_reference Signature, "
 							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 
 					// Account group add/remove admin transactions
-					stmt.execute("CREATE TABLE AddGroupAdminTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_name GroupName NOT NULL, address QoraAddress NOT NULL, "
+					stmt.execute(
-							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+							"CREATE TABLE AddGroupAdminTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_id GroupID NOT NULL, address QoraAddress NOT NULL, "
-					stmt.execute("CREATE TABLE RemoveGroupAdminTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_name GroupName NOT NULL, admin QoraAddress NOT NULL, "
+									+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
-							+ "group_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+					stmt.execute(
+							"CREATE TABLE RemoveGroupAdminTransactions (signature Signature, owner QoraPublicKey NOT NULL, group_id GroupID NOT NULL, admin QoraAddress NOT NULL, "
+									+ "admin_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 
 					// Account group join/leave transactions
-					stmt.execute("CREATE TABLE JoinGroupTransactions (signature Signature, joiner QoraPublicKey NOT NULL, group_name GroupName NOT NULL, "
+					stmt.execute("CREATE TABLE JoinGroupTransactions (signature Signature, joiner QoraPublicKey NOT NULL, group_id GroupID NOT NULL, "
-							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+							+ "invite_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
-					stmt.execute("CREATE TABLE LeaveGroupTransactions (signature Signature, leaver QoraPublicKey NOT NULL, group_name GroupName NOT NULL, "
+					stmt.execute("CREATE TABLE LeaveGroupTransactions (signature Signature, leaver QoraPublicKey NOT NULL, group_id GroupID NOT NULL, "
 							+ "member_reference Signature, admin_reference Signature, "
 							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 
 					// Account group kick transaction
-					stmt.execute("CREATE TABLE GroupKickTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_name GroupName NOT NULL, address QoraAddress NOT NULL, "
+					stmt.execute(
-							+ "reason VARCHAR(400), member_reference Signature, admin_reference Signature, "
+							"CREATE TABLE GroupKickTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_id GroupID NOT NULL, address QoraAddress NOT NULL, "
-							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+									+ "reason GroupReason, member_reference Signature, admin_reference Signature, join_reference Signature, "
+									+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 
 					// Account group invite/cancel-invite transactions
-					stmt.execute("CREATE TABLE GroupInviteTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_name GroupName NOT NULL, invitee QoraAddress NOT NULL, "
+					stmt.execute(
-							+ "time_to_live INTEGER NOT NULL, group_reference Signature, "
+							"CREATE TABLE GroupInviteTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_id GroupID NOT NULL, invitee QoraAddress NOT NULL, "
-							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+									+ "time_to_live INTEGER NOT NULL, join_reference Signature, "
-					// For finding invite transactions during orphaning
+									+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
-					stmt.execute("CREATE INDEX GroupInviteTransactionReferenceIndex ON GroupInviteTransactions (group_reference)");
 					// Cancel group invite
-					stmt.execute("CREATE TABLE CancelGroupInviteTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_name GroupName NOT NULL, invitee QoraAddress NOT NULL, "
+					stmt.execute(
-							+ "group_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+							"CREATE TABLE CancelGroupInviteTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_id GroupID NOT NULL, invitee QoraAddress NOT NULL, "
+									+ "invite_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 
-					// Account ban/unban transactions
+					// Account ban/cancel-ban transactions
-					stmt.execute("CREATE TABLE GroupBanTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_name GroupName NOT NULL, address QoraAddress NOT NULL, "
+					stmt.execute(
-							+ "reason VARCHAR(400), time_to_live INTEGER NOT NULL, member_reference Signature, admin_reference Signature, "
+							"CREATE TABLE GroupBanTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_id GroupID NOT NULL, address QoraAddress NOT NULL, "
-							+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+									+ "reason GroupReason, time_to_live INTEGER NOT NULL, "
-					stmt.execute("CREATE TABLE GroupUnbanTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_name GroupName NOT NULL, address QoraAddress NOT NULL, "
+									+ "member_reference Signature, admin_reference Signature, join_invite_reference Signature, "
-							+ "group_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+									+ "PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
+					stmt.execute(
+							"CREATE TABLE CancelGroupBanTransactions (signature Signature, admin QoraPublicKey NOT NULL, group_id GroupID NOT NULL, address QoraAddress NOT NULL, "
+									+ "ban_reference Signature, PRIMARY KEY (signature), FOREIGN KEY (signature) REFERENCES Transactions (signature) ON DELETE CASCADE)");
 					break;
 
 				default:

src/main/java/org/qora/repository/hsqldb/HSQLDBGroupRepository.java

@@ -27,33 +27,68 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	// Groups
 
 	@Override
-	public GroupData fromGroupName(String groupName) throws DataException {
+	public GroupData fromGroupId(int groupId) throws DataException {
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT owner, description, created, updated, reference, is_open FROM AccountGroups WHERE group_name = ?", groupName)) {
+				.checkedExecute("SELECT group_name, owner, description, created, updated, reference, is_open FROM Groups WHERE group_id = ?", groupId)) {
 			if (resultSet == null)
 				return null;
 
-			String owner = resultSet.getString(1);
+			String groupName = resultSet.getString(1);
-			String description = resultSet.getString(2);
+			String owner = resultSet.getString(2);
-			long created = resultSet.getTimestamp(3, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
+			String description = resultSet.getString(3);
+			long created = resultSet.getTimestamp(4, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
 
 			// Special handling for possibly-NULL "updated" column
-			Timestamp updatedTimestamp = resultSet.getTimestamp(4, Calendar.getInstance(HSQLDBRepository.UTC));
+			Timestamp updatedTimestamp = resultSet.getTimestamp(5, Calendar.getInstance(HSQLDBRepository.UTC));
 			Long updated = resultSet.wasNull() ? null : updatedTimestamp.getTime();
 
-			byte[] reference = resultSet.getBytes(5);
+			byte[] reference = resultSet.getBytes(6);
-			boolean isOpen = resultSet.getBoolean(6);
+			boolean isOpen = resultSet.getBoolean(7);
 
-			return new GroupData(owner, groupName, description, created, updated, isOpen, reference);
+			return new GroupData(groupId, owner, groupName, description, created, updated, isOpen, reference);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group info from repository", e);
 		}
 	}
 
+	@Override
+	public GroupData fromGroupName(String groupName) throws DataException {
+		try (ResultSet resultSet = this.repository
+				.checkedExecute("SELECT group_id, owner, description, created, updated, reference, is_open FROM Groups WHERE group_name = ?", groupName)) {
+			if (resultSet == null)
+				return null;
+
+			int groupId = resultSet.getInt(1);
+			String owner = resultSet.getString(2);
+			String description = resultSet.getString(3);
+			long created = resultSet.getTimestamp(4, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
+
+			// Special handling for possibly-NULL "updated" column
+			Timestamp updatedTimestamp = resultSet.getTimestamp(5, Calendar.getInstance(HSQLDBRepository.UTC));
+			Long updated = resultSet.wasNull() ? null : updatedTimestamp.getTime();
+
+			byte[] reference = resultSet.getBytes(6);
+			boolean isOpen = resultSet.getBoolean(7);
+
+			return new GroupData(groupId, owner, groupName, description, created, updated, isOpen, reference);
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch group info from repository", e);
+		}
+	}
+
+	@Override
+	public boolean groupExists(int groupId) throws DataException {
+		try {
+			return this.repository.exists("Groups", "group_id = ?", groupId);
+		} catch (SQLException e) {
+			throw new DataException("Unable to check for group in repository", e);
+		}
+	}
+
 	@Override
 	public boolean groupExists(String groupName) throws DataException {
 		try {
-			return this.repository.exists("AccountGroups", "group_name = ?", groupName);
+			return this.repository.exists("Groups", "group_name = ?", groupName);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group in repository", e);
 		}
@@ -64,24 +99,25 @@ public class HSQLDBGroupRepository implements GroupRepository {
 		List<GroupData> groups = new ArrayList<>();
 
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT group_name, description, owner, created, updated, reference, is_open FROM AccountGroups")) {
+				.checkedExecute("SELECT group_id, owner, group_name, description, created, updated, reference, is_open FROM Groups")) {
 			if (resultSet == null)
 				return groups;
 
 			do {
-				String groupName = resultSet.getString(1);
+				int groupId = resultSet.getInt(1);
-				String description = resultSet.getString(2);
+				String owner = resultSet.getString(2);
-				String owner = resultSet.getString(3);
+				String groupName = resultSet.getString(3);
-				long created = resultSet.getTimestamp(4, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
+				String description = resultSet.getString(4);
+				long created = resultSet.getTimestamp(5, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
 
 				// Special handling for possibly-NULL "updated" column
-				Timestamp updatedTimestamp = resultSet.getTimestamp(5, Calendar.getInstance(HSQLDBRepository.UTC));
+				Timestamp updatedTimestamp = resultSet.getTimestamp(6, Calendar.getInstance(HSQLDBRepository.UTC));
 				Long updated = resultSet.wasNull() ? null : updatedTimestamp.getTime();
 
-				byte[] reference = resultSet.getBytes(6);
+				byte[] reference = resultSet.getBytes(7);
-				boolean isOpen = resultSet.getBoolean(7);
+				boolean isOpen = resultSet.getBoolean(8);
 
-				groups.add(new GroupData(owner, groupName, description, created, updated, isOpen, reference));
+				groups.add(new GroupData(groupId, owner, groupName, description, created, updated, isOpen, reference));
 			} while (resultSet.next());
 
 			return groups;
@@ -95,23 +131,57 @@ public class HSQLDBGroupRepository implements GroupRepository {
 		List<GroupData> groups = new ArrayList<>();
 
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT group_name, description, created, updated, reference, is_open FROM AccountGroups WHERE owner = ?", owner)) {
+				.checkedExecute("SELECT group_id, group_name, description, created, updated, reference, is_open FROM Groups WHERE owner = ?", owner)) {
 			if (resultSet == null)
 				return groups;
 
 			do {
-				String groupName = resultSet.getString(1);
+				int groupId = resultSet.getInt(1);
-				String description = resultSet.getString(2);
+				String groupName = resultSet.getString(2);
-				long created = resultSet.getTimestamp(3, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
+				String description = resultSet.getString(3);
+				long created = resultSet.getTimestamp(4, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
 
 				// Special handling for possibly-NULL "updated" column
-				Timestamp updatedTimestamp = resultSet.getTimestamp(4, Calendar.getInstance(HSQLDBRepository.UTC));
+				Timestamp updatedTimestamp = resultSet.getTimestamp(5, Calendar.getInstance(HSQLDBRepository.UTC));
 				Long updated = updatedTimestamp == null ? null : updatedTimestamp.getTime();
 
-				byte[] reference = resultSet.getBytes(5);
+				byte[] reference = resultSet.getBytes(6);
-				boolean isOpen = resultSet.getBoolean(6);
+				boolean isOpen = resultSet.getBoolean(7);
 
-				groups.add(new GroupData(owner, groupName, description, created, updated, isOpen, reference));
+				groups.add(new GroupData(groupId, owner, groupName, description, created, updated, isOpen, reference));
+			} while (resultSet.next());
+
+			return groups;
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch account's groups from repository", e);
+		}
+	}
+
+	@Override
+	public List<GroupData> getGroupsWithMember(String member) throws DataException {
+		List<GroupData> groups = new ArrayList<>();
+
+		try (ResultSet resultSet = this.repository.checkedExecute(
+				"SELECT group_id, owner, group_name, description, created, updated, reference, is_open FROM Groups JOIN GroupMembers USING (group_id) WHERE address = ?",
+				member)) {
+			if (resultSet == null)
+				return groups;
+
+			do {
+				int groupId = resultSet.getInt(1);
+				String owner = resultSet.getString(2);
+				String groupName = resultSet.getString(3);
+				String description = resultSet.getString(4);
+				long created = resultSet.getTimestamp(5, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
+
+				// Special handling for possibly-NULL "updated" column
+				Timestamp updatedTimestamp = resultSet.getTimestamp(6, Calendar.getInstance(HSQLDBRepository.UTC));
+				Long updated = updatedTimestamp == null ? null : updatedTimestamp.getTime();
+
+				byte[] reference = resultSet.getBytes(7);
+				boolean isOpen = resultSet.getBoolean(8);
+
+				groups.add(new GroupData(groupId, owner, groupName, description, created, updated, isOpen, reference));
 			} while (resultSet.next());
 
 			return groups;
@@ -122,36 +192,48 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 	@Override
 	public void save(GroupData groupData) throws DataException {
-		HSQLDBSaver saveHelper = new HSQLDBSaver("AccountGroups");
+		HSQLDBSaver saveHelper = new HSQLDBSaver("Groups");
 
 		// Special handling for "updated" timestamp
 		Long updated = groupData.getUpdated();
 		Timestamp updatedTimestamp = updated == null ? null : new Timestamp(updated);
 
-		saveHelper.bind("owner", groupData.getOwner()).bind("group_name", groupData.getGroupName()).bind("description", groupData.getDescription())
+		saveHelper.bind("group_id", groupData.getGroupId()).bind("owner", groupData.getOwner()).bind("group_name", groupData.getGroupName())
-				.bind("created", new Timestamp(groupData.getCreated())).bind("updated", updatedTimestamp).bind("reference", groupData.getReference())
+				.bind("description", groupData.getDescription()).bind("created", new Timestamp(groupData.getCreated())).bind("updated", updatedTimestamp)
-				.bind("is_open", groupData.getIsOpen());
+				.bind("reference", groupData.getReference()).bind("is_open", groupData.getIsOpen());
 
 		try {
 			saveHelper.execute(this.repository);
+
+			if (groupData.getGroupId() == null) {
+				// Fetch new groupId
+				try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_id FROM Groups WHERE reference = ?", groupData.getReference())) {
+					if (resultSet == null)
+						throw new DataException("Unable to fetch new group ID from repository");
+
+					groupData.setGroupId(resultSet.getInt(1));
+				}
+			}
 		} catch (SQLException e) {
 			throw new DataException("Unable to save group info into repository", e);
 		}
 	}
 
+	@Override
+	public void delete(int groupId) throws DataException {
+		try {
+			// Remove group
+			this.repository.delete("Groups", "group_id = ?", groupId);
+		} catch (SQLException e) {
+			throw new DataException("Unable to delete group info from repository", e);
+		}
+	}
+
 	@Override
 	public void delete(String groupName) throws DataException {
 		try {
-			// Remove invites
-			this.repository.delete("AccountGroupInvites", "group_name = ?", groupName);
-			// Remove bans
-			this.repository.delete("AccountGroupBans", "group_name = ?", groupName);
-			// Remove members
-			this.repository.delete("AccountGroupMembers", "group_name = ?", groupName);
-			// Remove admins
-			this.repository.delete("AccountGroupAdmins", "group_name = ?", groupName);
 			// Remove group
-			this.repository.delete("AccountGroups", "group_name = ?", groupName);
+			this.repository.delete("Groups", "group_name = ?", groupName);
 		} catch (SQLException e) {
 			throw new DataException("Unable to delete group info from repository", e);
 		}
@@ -160,42 +242,42 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	// Group Admins
 
 	@Override
-	public GroupAdminData getAdmin(String groupName, String address) throws DataException {
+	public GroupAdminData getAdmin(int groupId, String address) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT admin, group_reference FROM AccountGroupAdmins WHERE group_name = ?", groupName)) {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT admin, reference FROM GroupAdmins WHERE group_id = ?", groupId)) {
 			if (resultSet == null)
 				return null;
 
 			String admin = resultSet.getString(1);
-			byte[] groupReference = resultSet.getBytes(2);
+			byte[] reference = resultSet.getBytes(2);
 
-			return new GroupAdminData(groupName, admin, groupReference);
+			return new GroupAdminData(groupId, admin, reference);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group admin from repository", e);
 		}
 	}
 
 	@Override
-	public boolean adminExists(String groupName, String address) throws DataException {
+	public boolean adminExists(int groupId, String address) throws DataException {
 		try {
-			return this.repository.exists("AccountGroupAdmins", "group_name = ? AND admin = ?", groupName, address);
+			return this.repository.exists("GroupAdmins", "group_id = ? AND admin = ?", groupId, address);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group admin in repository", e);
 		}
 	}
 
 	@Override
-	public List<GroupAdminData> getGroupAdmins(String groupName) throws DataException {
+	public List<GroupAdminData> getGroupAdmins(int groupId) throws DataException {
 		List<GroupAdminData> admins = new ArrayList<>();
 
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT admin, group_reference FROM AccountGroupAdmins WHERE group_name = ?", groupName)) {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT admin, reference FROM GroupAdmins WHERE group_id = ?", groupId)) {
 			if (resultSet == null)
 				return admins;
 
 			do {
 				String admin = resultSet.getString(1);
-				byte[] groupReference = resultSet.getBytes(2);
+				byte[] reference = resultSet.getBytes(2);
 
-				admins.add(new GroupAdminData(groupName, admin, groupReference));
+				admins.add(new GroupAdminData(groupId, admin, reference));
 			} while (resultSet.next());
 
 			return admins;
@@ -206,10 +288,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 	@Override
 	public void save(GroupAdminData groupAdminData) throws DataException {
-		HSQLDBSaver saveHelper = new HSQLDBSaver("AccountGroupAdmins");
+		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupAdmins");
 
-		saveHelper.bind("group_name", groupAdminData.getGroupName()).bind("admin", groupAdminData.getAdmin()).bind("group_reference",
+		saveHelper.bind("group_id", groupAdminData.getGroupId()).bind("admin", groupAdminData.getAdmin()).bind("reference", groupAdminData.getReference());
-				groupAdminData.getGroupReference());
 
 		try {
 			saveHelper.execute(this.repository);
@@ -219,9 +300,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public void deleteAdmin(String groupName, String address) throws DataException {
+	public void deleteAdmin(int groupId, String address) throws DataException {
 		try {
-			this.repository.delete("AccountGroupAdmins", "group_name = ? AND admin = ?", groupName, address);
+			this.repository.delete("GroupAdmins", "group_id = ? AND admin = ?", groupId, address);
 		} catch (SQLException e) {
 			throw new DataException("Unable to delete group admin info from repository", e);
 		}
@@ -230,46 +311,44 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	// Group Members
 
 	@Override
-	public GroupMemberData getMember(String groupName, String address) throws DataException {
+	public GroupMemberData getMember(int groupId, String address) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT address, joined, group_reference FROM AccountGroupMembers WHERE group_name = ?",
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT address, joined, reference FROM GroupMembers WHERE group_id = ?", groupId)) {
-				groupName)) {
 			if (resultSet == null)
 				return null;
 
 			String member = resultSet.getString(1);
 			long joined = resultSet.getTimestamp(2, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
-			byte[] groupReference = resultSet.getBytes(3);
+			byte[] reference = resultSet.getBytes(3);
 
-			return new GroupMemberData(groupName, member, joined, groupReference);
+			return new GroupMemberData(groupId, member, joined, reference);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group members from repository", e);
 		}
 	}
 
 	@Override
-	public boolean memberExists(String groupName, String address) throws DataException {
+	public boolean memberExists(int groupId, String address) throws DataException {
 		try {
-			return this.repository.exists("AccountGroupMembers", "group_name = ? AND address = ?", groupName, address);
+			return this.repository.exists("GroupMembers", "group_id = ? AND address = ?", groupId, address);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group member in repository", e);
 		}
 	}
 
 	@Override
-	public List<GroupMemberData> getGroupMembers(String groupName) throws DataException {
+	public List<GroupMemberData> getGroupMembers(int groupId) throws DataException {
 		List<GroupMemberData> members = new ArrayList<>();
 
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT address, joined, group_reference FROM AccountGroupMembers WHERE group_name = ?",
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT address, joined, reference FROM GroupMembers WHERE group_id = ?", groupId)) {
-				groupName)) {
 			if (resultSet == null)
 				return members;
 
 			do {
 				String member = resultSet.getString(1);
 				long joined = resultSet.getTimestamp(2, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
-				byte[] groupReference = resultSet.getBytes(3);
+				byte[] reference = resultSet.getBytes(3);
 
-				members.add(new GroupMemberData(groupName, member, joined, groupReference));
+				members.add(new GroupMemberData(groupId, member, joined, reference));
 			} while (resultSet.next());
 
 			return members;
@@ -279,9 +358,10 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public Integer countGroupMembers(String groupName) throws DataException {
+	public Integer countGroupMembers(int groupId) throws DataException {
-		try (ResultSet resultSet = this.repository
+		// "GROUP BY" clause required to avoid error "expression not in aggregate or GROUP BY columns: PUBLIC.GROUPS.GROUP_ID"
-				.checkedExecute("SELECT group_name, COUNT(*) FROM AccountGroupMembers WHERE group_name = ? GROUP BY group_name", groupName)) {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_id, COUNT(*) FROM GroupMembers WHERE group_id = ? GROUP BY group_id",
+				groupId)) {
 			if (resultSet == null)
 				return null;
 
@@ -293,10 +373,10 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 	@Override
 	public void save(GroupMemberData groupMemberData) throws DataException {
-		HSQLDBSaver saveHelper = new HSQLDBSaver("AccountGroupMembers");
+		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupMembers");
 
-		saveHelper.bind("group_name", groupMemberData.getGroupName()).bind("address", groupMemberData.getMember())
+		saveHelper.bind("group_id", groupMemberData.getGroupId()).bind("address", groupMemberData.getMember())
-				.bind("joined", new Timestamp(groupMemberData.getJoined())).bind("group_reference", groupMemberData.getGroupReference());
+				.bind("joined", new Timestamp(groupMemberData.getJoined())).bind("reference", groupMemberData.getReference());
 
 		try {
 			saveHelper.execute(this.repository);
@@ -306,9 +386,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public void deleteMember(String groupName, String address) throws DataException {
+	public void deleteMember(int groupId, String address) throws DataException {
 		try {
-			this.repository.delete("AccountGroupMembers", "group_name = ? AND address = ?", groupName, address);
+			this.repository.delete("GroupMembers", "group_id = ? AND address = ?", groupId, address);
 		} catch (SQLException e) {
 			throw new DataException("Unable to delete group member info from repository", e);
 		}
@@ -317,46 +397,38 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	// Group Invites
 
 	@Override
-	public GroupInviteData getInvite(String groupName, String inviter, String invitee) throws DataException {
+	public GroupInviteData getInvite(int groupId, String invitee) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT expiry, reference FROM AccountGroupInvites WHERE group_name = ?", groupName)) {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT inviter, expiry, reference FROM GroupInvites WHERE group_id = ? AND invitee = ?",
+				groupId, invitee)) {
 			if (resultSet == null)
 				return null;
 
-			Timestamp expiryTimestamp = resultSet.getTimestamp(1, Calendar.getInstance(HSQLDBRepository.UTC));
+			String inviter = resultSet.getString(1);
+			Timestamp expiryTimestamp = resultSet.getTimestamp(2, Calendar.getInstance(HSQLDBRepository.UTC));
 			Long expiry = expiryTimestamp == null ? null : expiryTimestamp.getTime();
 
-			byte[] reference = resultSet.getBytes(2);
+			byte[] reference = resultSet.getBytes(3);
 
-			return new GroupInviteData(groupName, inviter, invitee, expiry, reference);
+			return new GroupInviteData(groupId, inviter, invitee, expiry, reference);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group invite from repository", e);
 		}
 	}
 
 	@Override
-	public boolean inviteExists(String groupName, String invitee) throws DataException {
+	public boolean inviteExists(int groupId, String invitee) throws DataException {
 		try {
-			return this.repository.exists("AccountGroupInvites", "group_name = ? AND invitee = ?", groupName, invitee);
+			return this.repository.exists("GroupInvites", "group_id = ? AND invitee = ?", groupId, invitee);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group invite in repository", e);
 		}
 	}
 
 	@Override
-	public boolean inviteExists(String groupName, String inviter, String invitee) throws DataException {
+	public List<GroupInviteData> getGroupInvites(int groupId) throws DataException {
-		try {
-			return this.repository.exists("AccountGroupInvites", "group_name = ? AND inviter = ? AND invitee = ?", groupName, inviter, invitee);
-		} catch (SQLException e) {
-			throw new DataException("Unable to check for group invite in repository", e);
-		}
-	}
-
-	@Override
-	public List<GroupInviteData> getGroupInvites(String groupName) throws DataException {
 		List<GroupInviteData> invites = new ArrayList<>();
 
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT inviter, invitee, expiry, reference FROM AccountGroupInvites WHERE group_name = ?",
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT inviter, invitee, expiry, reference FROM GroupInvites WHERE group_id = ?", groupId)) {
-				groupName)) {
 			if (resultSet == null)
 				return invites;
 
@@ -369,7 +441,7 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 				byte[] reference = resultSet.getBytes(4);
 
-				invites.add(new GroupInviteData(groupName, inviter, invitee, expiry, reference));
+				invites.add(new GroupInviteData(groupId, inviter, invitee, expiry, reference));
 			} while (resultSet.next());
 
 			return invites;
@@ -379,23 +451,23 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public List<GroupInviteData> getInvitesByInvitee(String groupName, String invitee) throws DataException {
+	public List<GroupInviteData> getInvitesByInvitee(String invitee) throws DataException {
 		List<GroupInviteData> invites = new ArrayList<>();
 
-		try (ResultSet resultSet = this.repository
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_id, inviter, expiry, reference FROM GroupInvites WHERE invitee = ?", invitee)) {
-				.checkedExecute("SELECT inviter, expiry, reference FROM AccountGroupInvites WHERE group_name = ? AND invitee = ?", groupName, invitee)) {
 			if (resultSet == null)
 				return invites;
 
 			do {
-				String inviter = resultSet.getString(1);
+				int groupId = resultSet.getInt(1);
+				String inviter = resultSet.getString(2);
 
-				Timestamp expiryTimestamp = resultSet.getTimestamp(2, Calendar.getInstance(HSQLDBRepository.UTC));
+				Timestamp expiryTimestamp = resultSet.getTimestamp(3, Calendar.getInstance(HSQLDBRepository.UTC));
 				Long expiry = expiryTimestamp == null ? null : expiryTimestamp.getTime();
 
-				byte[] reference = resultSet.getBytes(3);
+				byte[] reference = resultSet.getBytes(4);
 
-				invites.add(new GroupInviteData(groupName, inviter, invitee, expiry, reference));
+				invites.add(new GroupInviteData(groupId, inviter, invitee, expiry, reference));
 			} while (resultSet.next());
 
 			return invites;
@@ -406,14 +478,14 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 	@Override
 	public void save(GroupInviteData groupInviteData) throws DataException {
-		HSQLDBSaver saveHelper = new HSQLDBSaver("AccountGroupInvites");
+		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupInvites");
 
 		Timestamp expiryTimestamp = null;
 		if (groupInviteData.getExpiry() != null)
 			expiryTimestamp = new Timestamp(groupInviteData.getExpiry());
 
-		saveHelper.bind("group_name", groupInviteData.getGroupName()).bind("inviter", groupInviteData.getInviter())
+		saveHelper.bind("group_id", groupInviteData.getGroupId()).bind("inviter", groupInviteData.getInviter()).bind("invitee", groupInviteData.getInvitee())
-				.bind("invitee", groupInviteData.getInvitee()).bind("expiry", expiryTimestamp).bind("reference", groupInviteData.getReference());
+				.bind("expiry", expiryTimestamp).bind("reference", groupInviteData.getReference());
 
 		try {
 			saveHelper.execute(this.repository);
@@ -423,9 +495,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public void deleteInvite(String groupName, String inviter, String invitee) throws DataException {
+	public void deleteInvite(int groupId, String invitee) throws DataException {
 		try {
-			this.repository.delete("AccountGroupInvites", "group_name = ? AND inviter = ? AND invitee = ?", groupName, inviter, invitee);
+			this.repository.delete("GroupInvites", "group_id = ? AND invitee = ?", groupId, invitee);
 		} catch (SQLException e) {
 			throw new DataException("Unable to delete group invite from repository", e);
 		}
@@ -434,26 +506,42 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	// Group Join Requests
 
 	@Override
-	public boolean joinRequestExists(String groupName, String joiner) throws DataException {
+	public GroupJoinRequestData getJoinRequest(Integer groupId, String joiner) throws DataException {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT reference FROM GroupJoinRequests WHERE group_id = ? AND joiner = ?", groupId,
+				joiner)) {
+			if (resultSet == null)
+				return null;
+
+			byte[] reference = resultSet.getBytes(1);
+
+			return new GroupJoinRequestData(groupId, joiner, reference);
+		} catch (SQLException e) {
+			throw new DataException("Unable to fetch group join requests from repository", e);
+		}
+	}
+
+	@Override
+	public boolean joinRequestExists(int groupId, String joiner) throws DataException {
 		try {
-			return this.repository.exists("AccountGroupJoinRequests", "group_name = ? AND joiner = ?", groupName, joiner);
+			return this.repository.exists("GroupJoinRequests", "group_id = ? AND joiner = ?", groupId, joiner);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group join request in repository", e);
 		}
 	}
 
 	@Override
-	public List<GroupJoinRequestData> getGroupJoinRequests(String groupName) throws DataException {
+	public List<GroupJoinRequestData> getGroupJoinRequests(int groupId) throws DataException {
 		List<GroupJoinRequestData> joinRequests = new ArrayList<>();
 
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT joiner FROM AccountGroupJoinRequests WHERE group_name = ?", groupName)) {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT joiner, reference FROM GroupJoinRequests WHERE group_id = ?", groupId)) {
 			if (resultSet == null)
 				return joinRequests;
 
 			do {
 				String joiner = resultSet.getString(1);
+				byte[] reference = resultSet.getBytes(2);
 
-				joinRequests.add(new GroupJoinRequestData(groupName, joiner));
+				joinRequests.add(new GroupJoinRequestData(groupId, joiner, reference));
 			} while (resultSet.next());
 
 			return joinRequests;
@@ -464,9 +552,10 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 	@Override
 	public void save(GroupJoinRequestData groupJoinRequestData) throws DataException {
-		HSQLDBSaver saveHelper = new HSQLDBSaver("AccountGroupJoinRequests");
+		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupJoinRequests");
 
-		saveHelper.bind("group_name", groupJoinRequestData.getGroupName()).bind("joiner", groupJoinRequestData.getJoiner());
+		saveHelper.bind("group_id", groupJoinRequestData.getGroupId()).bind("joiner", groupJoinRequestData.getJoiner()).bind("reference",
+				groupJoinRequestData.getReference());
 
 		try {
 			saveHelper.execute(this.repository);
@@ -476,9 +565,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public void deleteJoinRequest(String groupName, String joiner) throws DataException {
+	public void deleteJoinRequest(int groupId, String joiner) throws DataException {
 		try {
-			this.repository.delete("AccountGroupJoinRequests", "group_name = ? AND joiner = ?", groupName, joiner);
+			this.repository.delete("GroupJoinRequests", "group_id = ? AND joiner = ?", groupId, joiner);
 		} catch (SQLException e) {
 			throw new DataException("Unable to delete group join request from repository", e);
 		}
@@ -487,40 +576,39 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	// Group Bans
 
 	@Override
-	public GroupBanData getBan(String groupName, String member) throws DataException {
+	public GroupBanData getBan(int groupId, String offender) throws DataException {
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT offender, admin, banned, reason, expiry, reference FROM AccountGroupBans WHERE group_name = ?", groupName)) {
+				.checkedExecute("SELECT admin, banned, reason, expiry, reference FROM GroupBans WHERE group_id = ? AND offender = ?", groupId, offender)) {
-			String offender = resultSet.getString(1);
+			String admin = resultSet.getString(1);
-			String admin = resultSet.getString(2);
+			long banned = resultSet.getTimestamp(2, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
-			long banned = resultSet.getTimestamp(3, Calendar.getInstance(HSQLDBRepository.UTC)).getTime();
+			String reason = resultSet.getString(3);
-			String reason = resultSet.getString(4);
 
-			Timestamp expiryTimestamp = resultSet.getTimestamp(5, Calendar.getInstance(HSQLDBRepository.UTC));
+			Timestamp expiryTimestamp = resultSet.getTimestamp(4, Calendar.getInstance(HSQLDBRepository.UTC));
 			Long expiry = expiryTimestamp == null ? null : expiryTimestamp.getTime();
 
-			byte[] reference = resultSet.getBytes(6);
+			byte[] reference = resultSet.getBytes(5);
 
-			return new GroupBanData(groupName, offender, admin, banned, reason, expiry, reference);
+			return new GroupBanData(groupId, offender, admin, banned, reason, expiry, reference);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group bans from repository", e);
 		}
 	}
 
 	@Override
-	public boolean banExists(String groupName, String offender) throws DataException {
+	public boolean banExists(int groupId, String offender) throws DataException {
 		try {
-			return this.repository.exists("AccountGroupBans", "group_name = ? AND offender = ?", groupName, offender);
+			return this.repository.exists("GroupBans", "group_id = ? AND offender = ?", groupId, offender);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group ban in repository", e);
 		}
 	}
 
 	@Override
-	public List<GroupBanData> getGroupBans(String groupName) throws DataException {
+	public List<GroupBanData> getGroupBans(int groupId) throws DataException {
 		List<GroupBanData> bans = new ArrayList<>();
 
-		try (ResultSet resultSet = this.repository
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT offender, admin, banned, reason, expiry, reference FROM GroupBans WHERE group_id = ?",
-				.checkedExecute("SELECT offender, admin, banned, reason, expiry, reference FROM AccountGroupBans WHERE group_name = ?", groupName)) {
+				groupId)) {
 			if (resultSet == null)
 				return bans;
 
@@ -535,7 +623,7 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 				byte[] reference = resultSet.getBytes(6);
 
-				bans.add(new GroupBanData(groupName, offender, admin, banned, reason, expiry, reference));
+				bans.add(new GroupBanData(groupId, offender, admin, banned, reason, expiry, reference));
 			} while (resultSet.next());
 
 			return bans;
@@ -546,13 +634,13 @@ public class HSQLDBGroupRepository implements GroupRepository {
 
 	@Override
 	public void save(GroupBanData groupBanData) throws DataException {
-		HSQLDBSaver saveHelper = new HSQLDBSaver("AccountGroupBans");
+		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupBans");
 
 		Timestamp expiryTimestamp = null;
 		if (groupBanData.getExpiry() != null)
 			expiryTimestamp = new Timestamp(groupBanData.getExpiry());
 
-		saveHelper.bind("group_name", groupBanData.getGroupName()).bind("offender", groupBanData.getOffender()).bind("admin", groupBanData.getAdmin())
+		saveHelper.bind("group_id", groupBanData.getGroupId()).bind("offender", groupBanData.getOffender()).bind("admin", groupBanData.getAdmin())
 				.bind("banned", new Timestamp(groupBanData.getBanned())).bind("reason", groupBanData.getReason()).bind("expiry", expiryTimestamp)
 				.bind("reference", groupBanData.getReference());
 
@@ -564,9 +652,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public void deleteBan(String groupName, String offender) throws DataException {
+	public void deleteBan(int groupId, String offender) throws DataException {
 		try {
-			this.repository.delete("AccountGroupBans", "group_name = ? AND offender = ?", groupName, offender);
+			this.repository.delete("GroupBans", "group_id = ? AND offender = ?", groupId, offender);
 		} catch (SQLException e) {
 			throw new DataException("Unable to delete group ban from repository", e);
 		}

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBAddGroupAdminTransactionRepository.java

@@ -17,14 +17,14 @@ public class HSQLDBAddGroupAdminTransactionRepository extends HSQLDBTransactionR
 	}
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_name, address FROM AddGroupAdminTransactions WHERE signature = ?", signature)) {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_id, address FROM AddGroupAdminTransactions WHERE signature = ?", signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String member = resultSet.getString(2);
 
-			return new AddGroupAdminTransactionData(creatorPublicKey, groupName, member, fee, timestamp, reference, signature);
+			return new AddGroupAdminTransactionData(creatorPublicKey, groupId, member, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch add group admin transaction from repository", e);
 		}
@@ -37,7 +37,7 @@ public class HSQLDBAddGroupAdminTransactionRepository extends HSQLDBTransactionR
 		HSQLDBSaver saveHelper = new HSQLDBSaver("AddGroupAdminTransactions");
 
 		saveHelper.bind("signature", addGroupAdminTransactionData.getSignature()).bind("owner", addGroupAdminTransactionData.getOwnerPublicKey())
-				.bind("group_name", addGroupAdminTransactionData.getGroupName()).bind("address", addGroupAdminTransactionData.getMember());
+				.bind("group_id", addGroupAdminTransactionData.getGroupId()).bind("address", addGroupAdminTransactionData.getMember());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBCancelGroupBanTransactionRepository.java

@@ -4,29 +4,29 @@ import java.math.BigDecimal;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
-import org.qora.data.transaction.GroupUnbanTransactionData;
+import org.qora.data.transaction.CancelGroupBanTransactionData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.repository.DataException;
 import org.qora.repository.hsqldb.HSQLDBRepository;
 import org.qora.repository.hsqldb.HSQLDBSaver;
 
-public class HSQLDBGroupUnbanTransactionRepository extends HSQLDBTransactionRepository {
+public class HSQLDBCancelGroupBanTransactionRepository extends HSQLDBTransactionRepository {
 
-	public HSQLDBGroupUnbanTransactionRepository(HSQLDBRepository repository) {
+	public HSQLDBCancelGroupBanTransactionRepository(HSQLDBRepository repository) {
 		this.repository = repository;
 	}
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_name, address, group_reference FROM GroupUnbanTransactions WHERE signature = ?",
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_id, address, ban_reference FROM CancelGroupBanTransactions WHERE signature = ?",
 				signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String member = resultSet.getString(2);
-			byte[] groupReference = resultSet.getBytes(3);
+			byte[] banReference = resultSet.getBytes(3);
 
-			return new GroupUnbanTransactionData(creatorPublicKey, groupName, member, groupReference, fee, timestamp, reference, signature);
+			return new CancelGroupBanTransactionData(creatorPublicKey, groupId, member, banReference, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group unban transaction from repository", e);
 		}
@@ -34,13 +34,13 @@ public class HSQLDBGroupUnbanTransactionRepository extends HSQLDBTransactionRepo
 
 	@Override
 	public void save(TransactionData transactionData) throws DataException {
-		GroupUnbanTransactionData groupUnbanTransactionData = (GroupUnbanTransactionData) transactionData;
+		CancelGroupBanTransactionData groupUnbanTransactionData = (CancelGroupBanTransactionData) transactionData;
 
-		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupUnbanTransactions");
+		HSQLDBSaver saveHelper = new HSQLDBSaver("CancelGroupBanTransactions");
 
 		saveHelper.bind("signature", groupUnbanTransactionData.getSignature()).bind("admin", groupUnbanTransactionData.getAdminPublicKey())
-				.bind("group_name", groupUnbanTransactionData.getGroupName()).bind("address", groupUnbanTransactionData.getMember())
+				.bind("group_id", groupUnbanTransactionData.getGroupId()).bind("address", groupUnbanTransactionData.getMember())
-				.bind("group_reference", groupUnbanTransactionData.getGroupReference());
+				.bind("ban_reference", groupUnbanTransactionData.getBanReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBCancelGroupInviteTransactionRepository.java

@@ -18,14 +18,15 @@ public class HSQLDBCancelGroupInviteTransactionRepository extends HSQLDBTransact
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT group_name, invitee FROM CancelGroupInviteTransactions WHERE signature = ?", signature)) {
+				.checkedExecute("SELECT group_id, invitee, invite_reference FROM CancelGroupInviteTransactions WHERE signature = ?", signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String invitee = resultSet.getString(2);
+			byte[] inviteReference = resultSet.getBytes(3);
 
-			return new CancelGroupInviteTransactionData(creatorPublicKey, groupName, invitee, fee, timestamp, reference, signature);
+			return new CancelGroupInviteTransactionData(creatorPublicKey, groupId, invitee, inviteReference, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch cancel group invite transaction from repository", e);
 		}
@@ -38,7 +39,8 @@ public class HSQLDBCancelGroupInviteTransactionRepository extends HSQLDBTransact
 		HSQLDBSaver saveHelper = new HSQLDBSaver("CancelGroupInviteTransactions");
 
 		saveHelper.bind("signature", cancelGroupInviteTransactionData.getSignature()).bind("admin", cancelGroupInviteTransactionData.getAdminPublicKey())
-				.bind("group_name", cancelGroupInviteTransactionData.getGroupName()).bind("invitee", cancelGroupInviteTransactionData.getInvitee());
+				.bind("group_id", cancelGroupInviteTransactionData.getGroupId()).bind("invitee", cancelGroupInviteTransactionData.getInvitee())
+				.bind("invite_reference", cancelGroupInviteTransactionData.getInviteReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBCreateGroupTransactionRepository.java

@@ -17,8 +17,8 @@ public class HSQLDBCreateGroupTransactionRepository extends HSQLDBTransactionRep
 	}
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT owner, group_name, description, is_open FROM CreateGroupTransactions WHERE signature = ?",
+		try (ResultSet resultSet = this.repository
-				signature)) {
+				.checkedExecute("SELECT owner, group_name, description, is_open, group_id FROM CreateGroupTransactions WHERE signature = ?", signature)) {
 			if (resultSet == null)
 				return null;
 
@@ -27,7 +27,11 @@ public class HSQLDBCreateGroupTransactionRepository extends HSQLDBTransactionRep
 			String description = resultSet.getString(3);
 			boolean isOpen = resultSet.getBoolean(4);
 
-			return new CreateGroupTransactionData(creatorPublicKey, owner, groupName, description, isOpen, fee, timestamp, reference, signature);
+			Integer groupId = resultSet.getInt(5);
+			if (resultSet.wasNull())
+				groupId = null;
+
+			return new CreateGroupTransactionData(creatorPublicKey, owner, groupName, description, isOpen, groupId, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch create group transaction from repository", e);
 		}
@@ -41,7 +45,8 @@ public class HSQLDBCreateGroupTransactionRepository extends HSQLDBTransactionRep
 
 		saveHelper.bind("signature", createGroupTransactionData.getSignature()).bind("creator", createGroupTransactionData.getCreatorPublicKey())
 				.bind("owner", createGroupTransactionData.getOwner()).bind("group_name", createGroupTransactionData.getGroupName())
-				.bind("description", createGroupTransactionData.getDescription()).bind("is_open", createGroupTransactionData.getIsOpen());
+				.bind("description", createGroupTransactionData.getDescription()).bind("is_open", createGroupTransactionData.getIsOpen())
+				.bind("group_id", createGroupTransactionData.getGroupId());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBGroupBanTransactionRepository.java

@@ -18,20 +18,21 @@ public class HSQLDBGroupBanTransactionRepository extends HSQLDBTransactionReposi
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
 		try (ResultSet resultSet = this.repository.checkedExecute(
-				"SELECT group_name, address, reason, time_to_live, member_reference, admin_reference FROM GroupBanTransactions WHERE signature = ?",
+				"SELECT group_id, address, reason, time_to_live, member_reference, admin_reference, join_invite_reference FROM GroupBanTransactions WHERE signature = ?",
 				signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String offender = resultSet.getString(2);
 			String reason = resultSet.getString(3);
 			int timeToLive = resultSet.getInt(4);
 			byte[] memberReference = resultSet.getBytes(5);
 			byte[] adminReference = resultSet.getBytes(6);
+			byte[] joinInviteReference = resultSet.getBytes(7);
 
-			return new GroupBanTransactionData(creatorPublicKey, groupName, offender, reason, timeToLive, memberReference, adminReference, fee, timestamp,
+			return new GroupBanTransactionData(creatorPublicKey, groupId, offender, reason, timeToLive, memberReference, adminReference, joinInviteReference,
-					reference, signature);
+					fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group ban transaction from repository", e);
 		}
@@ -44,9 +45,10 @@ public class HSQLDBGroupBanTransactionRepository extends HSQLDBTransactionReposi
 		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupBanTransactions");
 
 		saveHelper.bind("signature", groupBanTransactionData.getSignature()).bind("admin", groupBanTransactionData.getAdminPublicKey())
-				.bind("group_name", groupBanTransactionData.getGroupName()).bind("address", groupBanTransactionData.getOffender())
+				.bind("group_id", groupBanTransactionData.getGroupId()).bind("address", groupBanTransactionData.getOffender())
 				.bind("reason", groupBanTransactionData.getReason()).bind("time_to_live", groupBanTransactionData.getTimeToLive())
-				.bind("member_reference", groupBanTransactionData.getMemberReference()).bind("admin_reference", groupBanTransactionData.getAdminReference());
+				.bind("member_reference", groupBanTransactionData.getMemberReference()).bind("admin_reference", groupBanTransactionData.getAdminReference())
+				.bind("join_invite_reference", groupBanTransactionData.getJoinInviteReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBGroupInviteTransactionRepository.java

@@ -3,8 +3,6 @@ package org.qora.repository.hsqldb.transaction;
 import java.math.BigDecimal;
 import java.sql.ResultSet;
 import java.sql.SQLException;
-import java.util.ArrayList;
-import java.util.List;
 
 import org.qora.data.transaction.GroupInviteTransactionData;
 import org.qora.data.transaction.TransactionData;
@@ -20,16 +18,16 @@ public class HSQLDBGroupInviteTransactionRepository extends HSQLDBTransactionRep
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT group_name, invitee, time_to_live, group_reference FROM GroupInviteTransactions WHERE signature = ?", signature)) {
+				.checkedExecute("SELECT group_id, invitee, time_to_live, join_reference FROM GroupInviteTransactions WHERE signature = ?", signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String invitee = resultSet.getString(2);
 			int timeToLive = resultSet.getInt(3);
-			byte[] groupReference = resultSet.getBytes(4);
+			byte[] joinReference = resultSet.getBytes(4);
 
-			return new GroupInviteTransactionData(creatorPublicKey, groupName, invitee, timeToLive, groupReference, fee, timestamp, reference, signature);
+			return new GroupInviteTransactionData(creatorPublicKey, groupId, invitee, timeToLive, joinReference, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group invite transaction from repository", e);
 		}
@@ -42,8 +40,8 @@ public class HSQLDBGroupInviteTransactionRepository extends HSQLDBTransactionRep
 		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupInviteTransactions");
 
 		saveHelper.bind("signature", groupInviteTransactionData.getSignature()).bind("admin", groupInviteTransactionData.getAdminPublicKey())
-				.bind("group_name", groupInviteTransactionData.getGroupName()).bind("invitee", groupInviteTransactionData.getInvitee())
+				.bind("group_id", groupInviteTransactionData.getGroupId()).bind("invitee", groupInviteTransactionData.getInvitee())
-				.bind("time_to_live", groupInviteTransactionData.getTimeToLive()).bind("group_reference", groupInviteTransactionData.getGroupReference());
+				.bind("time_to_live", groupInviteTransactionData.getTimeToLive()).bind("join_reference", groupInviteTransactionData.getJoinReference());
 
 		try {
 			saveHelper.execute(this.repository);
@@ -52,25 +50,4 @@ public class HSQLDBGroupInviteTransactionRepository extends HSQLDBTransactionRep
 		}
 	}
 
-	@Override
-	public List<GroupInviteTransactionData> getInvitesWithGroupReference(byte[] groupReference) throws DataException {
-		List<GroupInviteTransactionData> invites = new ArrayList<>();
-
-		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT signature FROM GroupInviteTransactions WHERE group_reference = ?", groupReference)) {
-			if (resultSet == null)
-				return invites;
-
-			do {
-				byte[] signature = resultSet.getBytes(1);
-
-				invites.add((GroupInviteTransactionData) this.repository.getTransactionRepository().fromSignature(signature));
-			} while (resultSet.next());
-
-			return invites;
-		} catch (SQLException e) {
-			throw new DataException("Unable to fetch group invite transaction from repository", e);
-		}
-	}
-
 }

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBGroupKickTransactionRepository.java

@@ -18,18 +18,20 @@ public class HSQLDBGroupKickTransactionRepository extends HSQLDBTransactionRepos
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
 		try (ResultSet resultSet = this.repository.checkedExecute(
-				"SELECT group_name, address, reason, member_reference, admin_reference FROM GroupKickTransactions WHERE signature = ?", signature)) {
+				"SELECT group_id, address, reason, member_reference, admin_reference, join_reference FROM GroupKickTransactions WHERE signature = ?",
+				signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String member = resultSet.getString(2);
 			String reason = resultSet.getString(3);
 			byte[] memberReference = resultSet.getBytes(4);
 			byte[] adminReference = resultSet.getBytes(5);
+			byte[] joinReference = resultSet.getBytes(6);
 
-			return new GroupKickTransactionData(creatorPublicKey, groupName, member, reason, memberReference, adminReference, fee, timestamp, reference,
+			return new GroupKickTransactionData(creatorPublicKey, groupId, member, reason, memberReference, adminReference, joinReference, fee, timestamp,
-					signature);
+					reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch group kick transaction from repository", e);
 		}
@@ -42,9 +44,9 @@ public class HSQLDBGroupKickTransactionRepository extends HSQLDBTransactionRepos
 		HSQLDBSaver saveHelper = new HSQLDBSaver("GroupKickTransactions");
 
 		saveHelper.bind("signature", groupKickTransactionData.getSignature()).bind("admin", groupKickTransactionData.getAdminPublicKey())
-				.bind("group_name", groupKickTransactionData.getGroupName()).bind("address", groupKickTransactionData.getMember())
+				.bind("group_id", groupKickTransactionData.getGroupId()).bind("address", groupKickTransactionData.getMember())
 				.bind("reason", groupKickTransactionData.getReason()).bind("member_reference", groupKickTransactionData.getMemberReference())
-				.bind("admin_reference", groupKickTransactionData.getAdminReference());
+				.bind("admin_reference", groupKickTransactionData.getAdminReference()).bind("join_reference", groupKickTransactionData.getJoinReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBJoinGroupTransactionRepository.java

@@ -17,13 +17,15 @@ public class HSQLDBJoinGroupTransactionRepository extends HSQLDBTransactionRepos
 	}
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_name FROM JoinGroupTransactions WHERE signature = ?", signature)) {
+		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_id, invite_reference FROM JoinGroupTransactions WHERE signature = ?",
+				signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
+			byte[] inviteReference = resultSet.getBytes(2);
 
-			return new JoinGroupTransactionData(creatorPublicKey, groupName, fee, timestamp, reference, signature);
+			return new JoinGroupTransactionData(creatorPublicKey, groupId, inviteReference, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch join group transaction from repository", e);
 		}
@@ -36,7 +38,7 @@ public class HSQLDBJoinGroupTransactionRepository extends HSQLDBTransactionRepos
 		HSQLDBSaver saveHelper = new HSQLDBSaver("JoinGroupTransactions");
 
 		saveHelper.bind("signature", joinGroupTransactionData.getSignature()).bind("joiner", joinGroupTransactionData.getJoinerPublicKey())
-				.bind("group_name", joinGroupTransactionData.getGroupName());
+				.bind("group_id", joinGroupTransactionData.getGroupId()).bind("invite_reference", joinGroupTransactionData.getInviteReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBLeaveGroupTransactionRepository.java

@@ -18,15 +18,15 @@ public class HSQLDBLeaveGroupTransactionRepository extends HSQLDBTransactionRepo
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT group_name, member_reference, admin_reference FROM LeaveGroupTransactions WHERE signature = ?", signature)) {
+				.checkedExecute("SELECT group_id, member_reference, admin_reference FROM LeaveGroupTransactions WHERE signature = ?", signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			byte[] memberReference = resultSet.getBytes(2);
 			byte[] adminReference = resultSet.getBytes(3);
 
-			return new LeaveGroupTransactionData(creatorPublicKey, groupName, memberReference, adminReference, fee, timestamp, reference, signature);
+			return new LeaveGroupTransactionData(creatorPublicKey, groupId, memberReference, adminReference, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch leave group transaction from repository", e);
 		}
@@ -39,7 +39,7 @@ public class HSQLDBLeaveGroupTransactionRepository extends HSQLDBTransactionRepo
 		HSQLDBSaver saveHelper = new HSQLDBSaver("LeaveGroupTransactions");
 
 		saveHelper.bind("signature", leaveGroupTransactionData.getSignature()).bind("leaver", leaveGroupTransactionData.getLeaverPublicKey())
-				.bind("group_name", leaveGroupTransactionData.getGroupName()).bind("member_reference", leaveGroupTransactionData.getMemberReference())
+				.bind("group_id", leaveGroupTransactionData.getGroupId()).bind("member_reference", leaveGroupTransactionData.getMemberReference())
 				.bind("admin_reference", leaveGroupTransactionData.getAdminReference());
 
 		try {

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBRemoveGroupAdminTransactionRepository.java

@@ -18,15 +18,15 @@ public class HSQLDBRemoveGroupAdminTransactionRepository extends HSQLDBTransacti
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
 		try (ResultSet resultSet = this.repository
-				.checkedExecute("SELECT group_name, admin, group_reference FROM RemoveGroupAdminTransactions WHERE signature = ?", signature)) {
+				.checkedExecute("SELECT group_id, admin, admin_reference FROM RemoveGroupAdminTransactions WHERE signature = ?", signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String admin = resultSet.getString(2);
-			byte[] groupReference = resultSet.getBytes(3);
+			byte[] adminReference = resultSet.getBytes(3);
 
-			return new RemoveGroupAdminTransactionData(creatorPublicKey, groupName, admin, groupReference, fee, timestamp, reference, signature);
+			return new RemoveGroupAdminTransactionData(creatorPublicKey, groupId, admin, adminReference, fee, timestamp, reference, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch remove group admin transaction from repository", e);
 		}
@@ -39,8 +39,8 @@ public class HSQLDBRemoveGroupAdminTransactionRepository extends HSQLDBTransacti
 		HSQLDBSaver saveHelper = new HSQLDBSaver("RemoveGroupAdminTransactions");
 
 		saveHelper.bind("signature", removeGroupAdminTransactionData.getSignature()).bind("owner", removeGroupAdminTransactionData.getOwnerPublicKey())
-				.bind("group_name", removeGroupAdminTransactionData.getGroupName()).bind("admin", removeGroupAdminTransactionData.getAdmin())
+				.bind("group_id", removeGroupAdminTransactionData.getGroupId()).bind("admin", removeGroupAdminTransactionData.getAdmin())
-				.bind("group_reference", removeGroupAdminTransactionData.getGroupReference());
+				.bind("admin_reference", removeGroupAdminTransactionData.getAdminReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBTransactionRepository.java

@@ -11,7 +11,6 @@ import java.util.List;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qora.data.PaymentData;
-import org.qora.data.transaction.GroupInviteTransactionData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.repository.DataException;
 import org.qora.repository.TransactionRepository;
@@ -47,7 +46,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 	private HSQLDBAddGroupAdminTransactionRepository addGroupAdminTransactionRepository;
 	private HSQLDBRemoveGroupAdminTransactionRepository removeGroupAdminTransactionRepository;
 	private HSQLDBGroupBanTransactionRepository groupBanTransactionRepository;
-	private HSQLDBGroupUnbanTransactionRepository groupUnbanTransactionRepository;
+	private HSQLDBCancelGroupBanTransactionRepository groupUnbanTransactionRepository;
 	private HSQLDBGroupKickTransactionRepository groupKickTransactionRepository;
 	private HSQLDBGroupInviteTransactionRepository groupInviteTransactionRepository;
 	private HSQLDBCancelGroupInviteTransactionRepository cancelGroupInviteTransactionRepository;
@@ -79,7 +78,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 		this.addGroupAdminTransactionRepository = new HSQLDBAddGroupAdminTransactionRepository(repository);
 		this.removeGroupAdminTransactionRepository = new HSQLDBRemoveGroupAdminTransactionRepository(repository);
 		this.groupBanTransactionRepository = new HSQLDBGroupBanTransactionRepository(repository);
-		this.groupUnbanTransactionRepository = new HSQLDBGroupUnbanTransactionRepository(repository);
+		this.groupUnbanTransactionRepository = new HSQLDBCancelGroupBanTransactionRepository(repository);
 		this.groupKickTransactionRepository = new HSQLDBGroupKickTransactionRepository(repository);
 		this.groupInviteTransactionRepository = new HSQLDBGroupInviteTransactionRepository(repository);
 		this.cancelGroupInviteTransactionRepository = new HSQLDBCancelGroupInviteTransactionRepository(repository);
@@ -226,7 +225,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 			case GROUP_BAN:
 				return this.groupBanTransactionRepository.fromBase(signature, reference, creatorPublicKey, timestamp, fee);
 
-			case GROUP_UNBAN:
+			case CANCEL_GROUP_BAN:
 				return this.groupUnbanTransactionRepository.fromBase(signature, reference, creatorPublicKey, timestamp, fee);
 
 			case GROUP_KICK:
@@ -584,7 +583,7 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 				this.groupBanTransactionRepository.save(transactionData);
 				break;
 
-			case GROUP_UNBAN:
+			case CANCEL_GROUP_BAN:
 				this.groupUnbanTransactionRepository.save(transactionData);
 				break;
 
@@ -629,10 +628,4 @@ public class HSQLDBTransactionRepository implements TransactionRepository {
 		}
 	}
 
-	@Override
-	public List<GroupInviteTransactionData> getInvitesWithGroupReference(byte[] groupReference) throws DataException {
-		// Let specialized subclass handle this
-		return this.groupInviteTransactionRepository.getInvitesWithGroupReference(groupReference);
-	}
-
 }

src/main/java/org/qora/repository/hsqldb/transaction/HSQLDBUpdateGroupTransactionRepository.java

@@ -17,18 +17,19 @@ public class HSQLDBUpdateGroupTransactionRepository extends HSQLDBTransactionRep
 	}
 
 	TransactionData fromBase(byte[] signature, byte[] reference, byte[] creatorPublicKey, long timestamp, BigDecimal fee) throws DataException {
-		try (ResultSet resultSet = this.repository.checkedExecute("SELECT group_name, new_owner, new_description, new_is_open, group_reference FROM UpdateGroupTransactions WHERE signature = ?",
+		try (ResultSet resultSet = this.repository.checkedExecute(
-				signature)) {
+				"SELECT group_id, new_owner, new_description, new_is_open, group_reference FROM UpdateGroupTransactions WHERE signature = ?", signature)) {
 			if (resultSet == null)
 				return null;
 
-			String groupName = resultSet.getString(1);
+			int groupId = resultSet.getInt(1);
 			String newOwner = resultSet.getString(2);
 			String newDescription = resultSet.getString(3);
 			boolean newIsOpen = resultSet.getBoolean(4);
 			byte[] groupReference = resultSet.getBytes(5);
 
-			return new UpdateGroupTransactionData(creatorPublicKey, groupName, newOwner, newDescription, newIsOpen, groupReference, fee, timestamp, reference, signature);
+			return new UpdateGroupTransactionData(creatorPublicKey, groupId, newOwner, newDescription, newIsOpen, groupReference, fee, timestamp, reference,
+					signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch update group transaction from repository", e);
 		}
@@ -41,7 +42,7 @@ public class HSQLDBUpdateGroupTransactionRepository extends HSQLDBTransactionRep
 		HSQLDBSaver saveHelper = new HSQLDBSaver("UpdateGroupTransactions");
 
 		saveHelper.bind("signature", updateGroupTransactionData.getSignature()).bind("owner", updateGroupTransactionData.getOwnerPublicKey())
-				.bind("group_name", updateGroupTransactionData.getGroupName()).bind("new_owner", updateGroupTransactionData.getNewOwner())
+				.bind("group_id", updateGroupTransactionData.getGroupId()).bind("new_owner", updateGroupTransactionData.getNewOwner())
 				.bind("new_description", updateGroupTransactionData.getNewDescription()).bind("new_is_open", updateGroupTransactionData.getNewIsOpen())
 				.bind("group_reference", updateGroupTransactionData.getGroupReference());
 

src/main/java/org/qora/transaction/AddGroupAdminTransaction.java

@@ -16,8 +16,6 @@ import org.qora.group.Group;
 import org.qora.repository.DataException;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class AddGroupAdminTransaction extends Transaction {
 
 	// Properties
@@ -76,16 +74,11 @@ public class AddGroupAdminTransaction extends Transaction {
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		// Check group name size bounds
+		// Check member address is valid
-		int groupNameLength = Utf8.encodedLength(addGroupAdminTransactionData.getGroupName());
+		if (!Crypto.isValidAddress(addGroupAdminTransactionData.getMember()))
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
+			return ValidationResult.INVALID_ADDRESS;
-			return ValidationResult.INVALID_NAME_LENGTH;
 
-		// Check group name is lowercase
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(addGroupAdminTransactionData.getGroupId());
-		if (!addGroupAdminTransactionData.getGroupName().equals(addGroupAdminTransactionData.getGroupName().toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = this.repository.getGroupRepository().fromGroupName(addGroupAdminTransactionData.getGroupName());
 
 		// Check group exists
 		if (groupData == null)
@@ -97,24 +90,21 @@ public class AddGroupAdminTransaction extends Transaction {
 		if (!owner.getAddress().equals(groupData.getOwner()))
 			return ValidationResult.INVALID_GROUP_OWNER;
 
-		// Check member address is valid
-		if (!Crypto.isValidAddress(addGroupAdminTransactionData.getMember()))
-			return ValidationResult.INVALID_ADDRESS;
-
 		Account member = getMember();
 
 		// Check address is a member
-		if (!this.repository.getGroupRepository().memberExists(addGroupAdminTransactionData.getGroupName(), member.getAddress()))
+		if (!this.repository.getGroupRepository().memberExists(addGroupAdminTransactionData.getGroupId(), member.getAddress()))
 			return ValidationResult.NOT_GROUP_MEMBER;
 
 		// Check member is not already an admin
-		if (this.repository.getGroupRepository().adminExists(addGroupAdminTransactionData.getGroupName(), member.getAddress()))
+		if (this.repository.getGroupRepository().adminExists(addGroupAdminTransactionData.getGroupId(), member.getAddress()))
 			return ValidationResult.ALREADY_GROUP_ADMIN;
 
 		// Check fee is positive
 		if (addGroupAdminTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// Check reference
 		if (!Arrays.equals(owner.getLastReference(), addGroupAdminTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
@@ -128,7 +118,7 @@ public class AddGroupAdminTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group adminship
-		Group group = new Group(this.repository, addGroupAdminTransactionData.getGroupName());
+		Group group = new Group(this.repository, addGroupAdminTransactionData.getGroupId());
 		group.promoteToAdmin(addGroupAdminTransactionData);
 
 		// Save this transaction
@@ -145,7 +135,7 @@ public class AddGroupAdminTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group adminship
-		Group group = new Group(this.repository, addGroupAdminTransactionData.getGroupName());
+		Group group = new Group(this.repository, addGroupAdminTransactionData.getGroupId());
 		group.unpromoteToAdmin(addGroupAdminTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/CancelGroupBanTransaction.java

@@ -9,27 +9,24 @@ import org.qora.account.Account;
 import org.qora.account.PublicKeyAccount;
 import org.qora.asset.Asset;
 import org.qora.crypto.Crypto;
-import org.qora.data.transaction.GroupUnbanTransactionData;
+import org.qora.data.transaction.CancelGroupBanTransactionData;
 import org.qora.data.group.GroupData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.group.Group;
 import org.qora.repository.DataException;
-import org.qora.repository.GroupRepository;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
+public class CancelGroupBanTransaction extends Transaction {
-
-public class GroupUnbanTransaction extends Transaction {
 
 	// Properties
-	private GroupUnbanTransactionData groupUnbanTransactionData;
+	private CancelGroupBanTransactionData groupUnbanTransactionData;
 
 	// Constructors
 
-	public GroupUnbanTransaction(Repository repository, TransactionData transactionData) {
+	public CancelGroupBanTransaction(Repository repository, TransactionData transactionData) {
 		super(repository, transactionData);
 
-		this.groupUnbanTransactionData = (GroupUnbanTransactionData) this.transactionData;
+		this.groupUnbanTransactionData = (CancelGroupBanTransactionData) this.transactionData;
 	}
 
 	// More information
@@ -77,43 +74,33 @@ public class GroupUnbanTransaction extends Transaction {
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupUnbanTransactionData.getGroupName();
-		
 		// Check member address is valid
 		if (!Crypto.isValidAddress(groupUnbanTransactionData.getMember()))
 			return ValidationResult.INVALID_ADDRESS;
 
-		// Check group name size bounds
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(groupUnbanTransactionData.getGroupId());
-		int groupNameLength = Utf8.encodedLength(groupName);
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!groupName.equals(groupName.toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = groupRepository.fromGroupName(groupName);
 
 		// Check group exists
 		if (groupData == null)
 			return ValidationResult.GROUP_DOES_NOT_EXIST;
 
 		Account admin = getAdmin();
-		Account member = getMember();
 
 		// Can't unban if not an admin
-		if (!groupRepository.adminExists(groupName, admin.getAddress()))
+		if (!this.repository.getGroupRepository().adminExists(groupUnbanTransactionData.getGroupId(), admin.getAddress()))
 			return ValidationResult.NOT_GROUP_ADMIN;
 
+		Account member = getMember();
+
 		// Check ban actually exists
-		if (!groupRepository.banExists(groupName, member.getAddress()))
+		if (!this.repository.getGroupRepository().banExists(groupUnbanTransactionData.getGroupId(), member.getAddress()))
 			return ValidationResult.BAN_UNKNOWN;
 
 		// Check fee is positive
 		if (groupUnbanTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// Check reference
 		if (!Arrays.equals(admin.getLastReference(), groupUnbanTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
@@ -127,7 +114,7 @@ public class GroupUnbanTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group Membership
-		Group group = new Group(this.repository, groupUnbanTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupUnbanTransactionData.getGroupId());
 		group.cancelBan(groupUnbanTransactionData);
 
 		// Save this transaction with updated member/admin references to transactions that can help restore state
@@ -144,7 +131,7 @@ public class GroupUnbanTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group membership
-		Group group = new Group(this.repository, groupUnbanTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupUnbanTransactionData.getGroupId());
 		group.uncancelBan(groupUnbanTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/CancelGroupInviteTransaction.java

@@ -14,22 +14,19 @@ import org.qora.data.group.GroupData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.group.Group;
 import org.qora.repository.DataException;
-import org.qora.repository.GroupRepository;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class CancelGroupInviteTransaction extends Transaction {
 
 	// Properties
-	private CancelGroupInviteTransactionData cancelCancelGroupInviteTransactionData;
+	private CancelGroupInviteTransactionData cancelGroupInviteTransactionData;
 
 	// Constructors
 
 	public CancelGroupInviteTransaction(Repository repository, TransactionData transactionData) {
 		super(repository, transactionData);
 
-		this.cancelCancelGroupInviteTransactionData = (CancelGroupInviteTransactionData) this.transactionData;
+		this.cancelGroupInviteTransactionData = (CancelGroupInviteTransactionData) this.transactionData;
 	}
 
 	// More information
@@ -66,55 +63,49 @@ public class CancelGroupInviteTransaction extends Transaction {
 	// Navigation
 
 	public Account getAdmin() throws DataException {
-		return new PublicKeyAccount(this.repository, this.cancelCancelGroupInviteTransactionData.getAdminPublicKey());
+		return new PublicKeyAccount(this.repository, this.cancelGroupInviteTransactionData.getAdminPublicKey());
 	}
 
 	public Account getInvitee() throws DataException {
-		return new Account(this.repository, this.cancelCancelGroupInviteTransactionData.getInvitee());
+		return new Account(this.repository, this.cancelGroupInviteTransactionData.getInvitee());
 	}
 
 	// Processing
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
+		// Check invitee address is valid
-		String groupName = cancelCancelGroupInviteTransactionData.getGroupName();
+		if (!Crypto.isValidAddress(cancelGroupInviteTransactionData.getInvitee()))
-
-		// Check member address is valid
-		if (!Crypto.isValidAddress(cancelCancelGroupInviteTransactionData.getInvitee()))
 			return ValidationResult.INVALID_ADDRESS;
 
-		// Check group name size bounds
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(cancelGroupInviteTransactionData.getGroupId());
-		int groupNameLength = Utf8.encodedLength(groupName);
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!groupName.equals(groupName.toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = groupRepository.fromGroupName(groupName);
 
 		// Check group exists
 		if (groupData == null)
 			return ValidationResult.GROUP_DOES_NOT_EXIST;
 
 		Account admin = getAdmin();
+
+		// Check admin is actually an admin
+		if (!this.repository.getGroupRepository().adminExists(cancelGroupInviteTransactionData.getGroupId(), admin.getAddress()))
+			return ValidationResult.NOT_GROUP_ADMIN;
+
 		Account invitee = getInvitee();
 
 		// Check invite exists
-		if (!groupRepository.inviteExists(groupName, admin.getAddress(), invitee.getAddress()))
+		if (!this.repository.getGroupRepository().inviteExists(cancelGroupInviteTransactionData.getGroupId(), invitee.getAddress()))
 			return ValidationResult.INVITE_UNKNOWN;
 
 		// Check fee is positive
-		if (cancelCancelGroupInviteTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
+		if (cancelGroupInviteTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
-		if (!Arrays.equals(admin.getLastReference(), cancelCancelGroupInviteTransactionData.getReference()))
+		// Check reference
+		if (!Arrays.equals(admin.getLastReference(), cancelGroupInviteTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
 		// Check creator has enough funds
-		if (admin.getConfirmedBalance(Asset.QORA).compareTo(cancelCancelGroupInviteTransactionData.getFee()) < 0)
+		if (admin.getConfirmedBalance(Asset.QORA).compareTo(cancelGroupInviteTransactionData.getFee()) < 0)
 			return ValidationResult.NO_BALANCE;
 
 		return ValidationResult.OK;
@@ -123,35 +114,35 @@ public class CancelGroupInviteTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group Membership
-		Group group = new Group(this.repository, cancelCancelGroupInviteTransactionData.getGroupName());
+		Group group = new Group(this.repository, cancelGroupInviteTransactionData.getGroupId());
-		group.cancelInvite(cancelCancelGroupInviteTransactionData);
+		group.cancelInvite(cancelGroupInviteTransactionData);
 
 		// Save this transaction with updated member/admin references to transactions that can help restore state
-		this.repository.getTransactionRepository().save(cancelCancelGroupInviteTransactionData);
+		this.repository.getTransactionRepository().save(cancelGroupInviteTransactionData);
 
 		// Update admin's balance
 		Account admin = getAdmin();
-		admin.setConfirmedBalance(Asset.QORA, admin.getConfirmedBalance(Asset.QORA).subtract(cancelCancelGroupInviteTransactionData.getFee()));
+		admin.setConfirmedBalance(Asset.QORA, admin.getConfirmedBalance(Asset.QORA).subtract(cancelGroupInviteTransactionData.getFee()));
 
 		// Update admin's reference
-		admin.setLastReference(cancelCancelGroupInviteTransactionData.getSignature());
+		admin.setLastReference(cancelGroupInviteTransactionData.getSignature());
 	}
 
 	@Override
 	public void orphan() throws DataException {
 		// Revert group membership
-		Group group = new Group(this.repository, cancelCancelGroupInviteTransactionData.getGroupName());
+		Group group = new Group(this.repository, cancelGroupInviteTransactionData.getGroupId());
-		group.uncancelInvite(cancelCancelGroupInviteTransactionData);
+		group.uncancelInvite(cancelGroupInviteTransactionData);
 
 		// Delete this transaction itself
-		this.repository.getTransactionRepository().delete(cancelCancelGroupInviteTransactionData);
+		this.repository.getTransactionRepository().delete(cancelGroupInviteTransactionData);
 
 		// Update admin's balance
 		Account admin = getAdmin();
-		admin.setConfirmedBalance(Asset.QORA, admin.getConfirmedBalance(Asset.QORA).add(cancelCancelGroupInviteTransactionData.getFee()));
+		admin.setConfirmedBalance(Asset.QORA, admin.getConfirmedBalance(Asset.QORA).add(cancelGroupInviteTransactionData.getFee()));
 
 		// Update admin's reference
-		admin.setLastReference(cancelCancelGroupInviteTransactionData.getReference());
+		admin.setLastReference(cancelGroupInviteTransactionData.getReference());
 	}
 
 }

src/main/java/org/qora/transaction/CreateGroupTransaction.java

@@ -96,9 +96,9 @@ public class CreateGroupTransaction extends Transaction {
 		if (createGroupTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
-		// Check reference is correct
 		Account creator = getCreator();
 
+		// Check reference is correct
 		if (!Arrays.equals(creator.getLastReference(), createGroupTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
@@ -115,6 +115,9 @@ public class CreateGroupTransaction extends Transaction {
 		Group group = new Group(this.repository, createGroupTransactionData);
 		group.create(createGroupTransactionData);
 
+		// Note newly assigned group ID in our transaction record
+		createGroupTransactionData.setGroupId(group.getGroupData().getGroupId());
+
 		// Save this transaction
 		this.repository.getTransactionRepository().save(createGroupTransactionData);
 
@@ -129,7 +132,7 @@ public class CreateGroupTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Uncreate group
-		Group group = new Group(this.repository, createGroupTransactionData.getGroupName());
+		Group group = new Group(this.repository, createGroupTransactionData.getGroupId());
 		group.uncreate();
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/GroupBanTransaction.java

@@ -14,11 +14,8 @@ import org.qora.data.group.GroupData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.group.Group;
 import org.qora.repository.DataException;
-import org.qora.repository.GroupRepository;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class GroupBanTransaction extends Transaction {
 
 	// Properties
@@ -77,47 +74,38 @@ public class GroupBanTransaction extends Transaction {
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
+		// Check offender address is valid
-		String groupName = groupBanTransactionData.getGroupName();
-		
-		// Check member address is valid
 		if (!Crypto.isValidAddress(groupBanTransactionData.getOffender()))
 			return ValidationResult.INVALID_ADDRESS;
 
-		// Check group name size bounds
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(groupBanTransactionData.getGroupId());
-		int groupNameLength = Utf8.encodedLength(groupName);
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!groupName.equals(groupName.toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = groupRepository.fromGroupName(groupName);
 
 		// Check group exists
 		if (groupData == null)
 			return ValidationResult.GROUP_DOES_NOT_EXIST;
 
 		Account admin = getAdmin();
-		Account member = getOffender();
 
 		// Can't ban if not an admin
-		if (!groupRepository.adminExists(groupName, admin.getAddress()))
+		if (!this.repository.getGroupRepository().adminExists(groupBanTransactionData.getGroupId(), admin.getAddress()))
 			return ValidationResult.NOT_GROUP_ADMIN;
 
+		Account offender = getOffender();
+
 		// Can't ban another admin unless the group owner
-		if (!admin.getAddress().equals(groupData.getOwner()) && groupRepository.adminExists(groupName, member.getAddress()))
+		if (!admin.getAddress().equals(groupData.getOwner())
+				&& this.repository.getGroupRepository().adminExists(groupBanTransactionData.getGroupId(), offender.getAddress()))
 			return ValidationResult.INVALID_GROUP_OWNER;
 
 		// Check fee is positive
 		if (groupBanTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// Check reference
 		if (!Arrays.equals(admin.getLastReference(), groupBanTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
-		// Check creator has enough funds
+		// Check admin has enough funds
 		if (admin.getConfirmedBalance(Asset.QORA).compareTo(groupBanTransactionData.getFee()) < 0)
 			return ValidationResult.NO_BALANCE;
 
@@ -127,7 +115,7 @@ public class GroupBanTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group Membership
-		Group group = new Group(this.repository, groupBanTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupBanTransactionData.getGroupId());
 		group.ban(groupBanTransactionData);
 
 		// Save this transaction with updated member/admin references to transactions that can help restore state
@@ -144,7 +132,7 @@ public class GroupBanTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group membership
-		Group group = new Group(this.repository, groupBanTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupBanTransactionData.getGroupId());
 		group.unban(groupBanTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/GroupInviteTransaction.java

@@ -14,11 +14,8 @@ import org.qora.data.group.GroupData;
 import org.qora.data.transaction.TransactionData;
 import org.qora.group.Group;
 import org.qora.repository.DataException;
-import org.qora.repository.GroupRepository;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class GroupInviteTransaction extends Transaction {
 
 	// Properties
@@ -77,9 +74,6 @@ public class GroupInviteTransaction extends Transaction {
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupInviteTransactionData.getGroupName();
-
 		// Check time to live zero (infinite) or positive
 		if (groupInviteTransactionData.getTimeToLive() < 0)
 			return ValidationResult.INVALID_LIFETIME;
@@ -88,36 +82,33 @@ public class GroupInviteTransaction extends Transaction {
 		if (!Crypto.isValidAddress(groupInviteTransactionData.getInvitee()))
 			return ValidationResult.INVALID_ADDRESS;
 
-		// Check group name size bounds
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(groupInviteTransactionData.getGroupId());
-		int groupNameLength = Utf8.encodedLength(groupName);
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!groupName.equals(groupName.toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = groupRepository.fromGroupName(groupName);
 
 		// Check group exists
 		if (groupData == null)
 			return ValidationResult.GROUP_DOES_NOT_EXIST;
 
 		Account admin = getAdmin();
-		Account invitee = getInvitee();
 
 		// Can't invite if not an admin
-		if (!groupRepository.adminExists(groupName, admin.getAddress()))
+		if (!this.repository.getGroupRepository().adminExists(groupInviteTransactionData.getGroupId(), admin.getAddress()))
 			return ValidationResult.NOT_GROUP_ADMIN;
 
+		Account invitee = getInvitee();
+
 		// Check invitee not already in group
-		if (groupRepository.memberExists(groupName, invitee.getAddress()))
+		if (this.repository.getGroupRepository().memberExists(groupInviteTransactionData.getGroupId(), invitee.getAddress()))
 			return ValidationResult.ALREADY_GROUP_MEMBER;
 
+		// Check invitee is not banned
+		if (this.repository.getGroupRepository().banExists(groupInviteTransactionData.getGroupId(), invitee.getAddress()))
+			return ValidationResult.BANNED_FROM_GROUP;
+
 		// Check fee is positive
 		if (groupInviteTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// Check reference
 		if (!Arrays.equals(admin.getLastReference(), groupInviteTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
@@ -131,7 +122,7 @@ public class GroupInviteTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group Membership
-		Group group = new Group(this.repository, groupInviteTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupInviteTransactionData.getGroupId());
 		group.invite(groupInviteTransactionData);
 
 		// Save this transaction with updated member/admin references to transactions that can help restore state
@@ -148,7 +139,7 @@ public class GroupInviteTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group membership
-		Group group = new Group(this.repository, groupInviteTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupInviteTransactionData.getGroupId());
 		group.uninvite(groupInviteTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/GroupKickTransaction.java

@@ -17,8 +17,6 @@ import org.qora.repository.DataException;
 import org.qora.repository.GroupRepository;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class GroupKickTransaction extends Transaction {
 
 	// Properties
@@ -77,47 +75,39 @@ public class GroupKickTransaction extends Transaction {
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		GroupRepository groupRepository = this.repository.getGroupRepository();
-		String groupName = groupKickTransactionData.getGroupName();
-		
 		// Check member address is valid
 		if (!Crypto.isValidAddress(groupKickTransactionData.getMember()))
 			return ValidationResult.INVALID_ADDRESS;
 
-		// Check group name size bounds
+		GroupRepository groupRepository = this.repository.getGroupRepository();
-		int groupNameLength = Utf8.encodedLength(groupName);
+		int groupId = groupKickTransactionData.getGroupId();
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
+		GroupData groupData = groupRepository.fromGroupId(groupId);
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!groupName.equals(groupName.toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = groupRepository.fromGroupName(groupName);
 
 		// Check group exists
 		if (groupData == null)
 			return ValidationResult.GROUP_DOES_NOT_EXIST;
 
 		Account admin = getAdmin();
-		Account member = getMember();
 
 		// Can't kick if not an admin
-		if (!groupRepository.adminExists(groupName, admin.getAddress()))
+		if (!groupRepository.adminExists(groupId, admin.getAddress()))
 			return ValidationResult.NOT_GROUP_ADMIN;
 
+		Account member = getMember();
+
 		// Check member actually in group UNLESS there's a pending join request
-		if (!groupRepository.joinRequestExists(groupName, member.getAddress()) && !groupRepository.memberExists(groupName, member.getAddress()))
+		if (!groupRepository.joinRequestExists(groupId, member.getAddress()) && !groupRepository.memberExists(groupId, member.getAddress()))
 			return ValidationResult.NOT_GROUP_MEMBER;
 
 		// Can't kick another admin unless the group owner
-		if (!admin.getAddress().equals(groupData.getOwner()) && groupRepository.adminExists(groupName, member.getAddress()))
+		if (!admin.getAddress().equals(groupData.getOwner()) && groupRepository.adminExists(groupId, member.getAddress()))
 			return ValidationResult.INVALID_GROUP_OWNER;
 
 		// Check fee is positive
 		if (groupKickTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// Check reference
 		if (!Arrays.equals(admin.getLastReference(), groupKickTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
@@ -131,7 +121,7 @@ public class GroupKickTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group Membership
-		Group group = new Group(this.repository, groupKickTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupKickTransactionData.getGroupId());
 		group.kick(groupKickTransactionData);
 
 		// Save this transaction with updated member/admin references to transactions that can help restore state
@@ -148,7 +138,7 @@ public class GroupKickTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group membership
-		Group group = new Group(this.repository, groupKickTransactionData.getGroupName());
+		Group group = new Group(this.repository, groupKickTransactionData.getGroupId());
 		group.unkick(groupKickTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/IssueAssetTransaction.java

@@ -161,7 +161,7 @@ public class IssueAssetTransaction extends Transaction {
 		Account owner = getOwner();
 		owner.deleteBalance(issueAssetTransactionData.getAssetId());
 
-		// Issue asset
+		// Deissue asset
 		Asset asset = new Asset(this.repository, issueAssetTransactionData.getAssetId());
 		asset.deissue();
 

src/main/java/org/qora/transaction/JoinGroupTransaction.java

@@ -15,8 +15,6 @@ import org.qora.group.Group;
 import org.qora.repository.DataException;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class JoinGroupTransaction extends Transaction {
 
 	// Properties
@@ -68,16 +66,7 @@ public class JoinGroupTransaction extends Transaction {
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		// Check group name size bounds
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(joinGroupTransactionData.getGroupId());
-		int groupNameLength = Utf8.encodedLength(joinGroupTransactionData.getGroupName());
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!joinGroupTransactionData.getGroupName().equals(joinGroupTransactionData.getGroupName().toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = this.repository.getGroupRepository().fromGroupName(joinGroupTransactionData.getGroupName());
 
 		// Check group exists
 		if (groupData == null)
@@ -85,13 +74,17 @@ public class JoinGroupTransaction extends Transaction {
 
 		Account joiner = getJoiner();
 
-		if (this.repository.getGroupRepository().memberExists(joinGroupTransactionData.getGroupName(), joiner.getAddress()))
+		if (this.repository.getGroupRepository().memberExists(joinGroupTransactionData.getGroupId(), joiner.getAddress()))
 			return ValidationResult.ALREADY_GROUP_MEMBER;
 
 		// Check member is not banned
-		if (this.repository.getGroupRepository().banExists(joinGroupTransactionData.getGroupName(), joiner.getAddress()))
+		if (this.repository.getGroupRepository().banExists(joinGroupTransactionData.getGroupId(), joiner.getAddress()))
 			return ValidationResult.BANNED_FROM_GROUP;
 
+		// Check join request doesn't already exist
+		if (this.repository.getGroupRepository().joinRequestExists(joinGroupTransactionData.getGroupId(), joiner.getAddress()))
+			return ValidationResult.JOIN_REQUEST_EXISTS;
+
 		// Check fee is positive
 		if (joinGroupTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
@@ -109,7 +102,7 @@ public class JoinGroupTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group Membership
-		Group group = new Group(this.repository, joinGroupTransactionData.getGroupName());
+		Group group = new Group(this.repository, joinGroupTransactionData.getGroupId());
 		group.join(joinGroupTransactionData);
 
 		// Save this transaction
@@ -126,7 +119,7 @@ public class JoinGroupTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group membership
-		Group group = new Group(this.repository, joinGroupTransactionData.getGroupName());
+		Group group = new Group(this.repository, joinGroupTransactionData.getGroupId());
 		group.unjoin(joinGroupTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/LeaveGroupTransaction.java

@@ -15,8 +15,6 @@ import org.qora.group.Group;
 import org.qora.repository.DataException;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class LeaveGroupTransaction extends Transaction {
 
 	// Properties
@@ -68,16 +66,7 @@ public class LeaveGroupTransaction extends Transaction {
 
 	@Override
 	public ValidationResult isValid() throws DataException {
-		// Check group name size bounds
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(leaveGroupTransactionData.getGroupId());
-		int groupNameLength = Utf8.encodedLength(leaveGroupTransactionData.getGroupName());
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!leaveGroupTransactionData.getGroupName().equals(leaveGroupTransactionData.getGroupName().toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = this.repository.getGroupRepository().fromGroupName(leaveGroupTransactionData.getGroupName());
 
 		// Check group exists
 		if (groupData == null)
@@ -89,13 +78,15 @@ public class LeaveGroupTransaction extends Transaction {
 		if (leaver.getAddress().equals(groupData.getOwner()))
 			return ValidationResult.GROUP_OWNER_CANNOT_LEAVE;
 
-		if (!this.repository.getGroupRepository().memberExists(leaveGroupTransactionData.getGroupName(), leaver.getAddress()))
+		// Check leaver is actually a member of group
+		if (!this.repository.getGroupRepository().memberExists(leaveGroupTransactionData.getGroupId(), leaver.getAddress()))
 			return ValidationResult.NOT_GROUP_MEMBER;
 
 		// Check fee is positive
 		if (leaveGroupTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// Check reference
 		if (!Arrays.equals(leaver.getLastReference(), leaveGroupTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
@@ -109,7 +100,7 @@ public class LeaveGroupTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group Membership
-		Group group = new Group(this.repository, leaveGroupTransactionData.getGroupName());
+		Group group = new Group(this.repository, leaveGroupTransactionData.getGroupId());
 		group.leave(leaveGroupTransactionData);
 
 		// Save this transaction with updated member/admin references to transactions that can help restore state
@@ -126,7 +117,7 @@ public class LeaveGroupTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group membership
-		Group group = new Group(this.repository, leaveGroupTransactionData.getGroupName());
+		Group group = new Group(this.repository, leaveGroupTransactionData.getGroupId());
 		group.unleave(leaveGroupTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/RemoveGroupAdminTransaction.java

@@ -16,8 +16,6 @@ import org.qora.group.Group;
 import org.qora.repository.DataException;
 import org.qora.repository.Repository;
 
-import com.google.common.base.Utf8;
-
 public class RemoveGroupAdminTransaction extends Transaction {
 
 	// Properties
@@ -80,16 +78,7 @@ public class RemoveGroupAdminTransaction extends Transaction {
 		if (!Crypto.isValidAddress(removeGroupAdminTransactionData.getAdmin()))
 			return ValidationResult.INVALID_ADDRESS;
 
-		// Check group name size bounds
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(removeGroupAdminTransactionData.getGroupId());
-		int groupNameLength = Utf8.encodedLength(removeGroupAdminTransactionData.getGroupName());
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
-		// Check group name is lowercase
-		if (!removeGroupAdminTransactionData.getGroupName().equals(removeGroupAdminTransactionData.getGroupName().toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = this.repository.getGroupRepository().fromGroupName(removeGroupAdminTransactionData.getGroupName());
 
 		// Check group exists
 		if (groupData == null)
@@ -104,13 +93,14 @@ public class RemoveGroupAdminTransaction extends Transaction {
 		Account admin = getAdmin();
 
 		// Check member is an admin
-		if (!this.repository.getGroupRepository().adminExists(removeGroupAdminTransactionData.getGroupName(), admin.getAddress()))
+		if (!this.repository.getGroupRepository().adminExists(removeGroupAdminTransactionData.getGroupId(), admin.getAddress()))
 			return ValidationResult.NOT_GROUP_ADMIN;
 
 		// Check fee is positive
 		if (removeGroupAdminTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// Check reference
 		if (!Arrays.equals(owner.getLastReference(), removeGroupAdminTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
@@ -124,7 +114,7 @@ public class RemoveGroupAdminTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group adminship
-		Group group = new Group(this.repository, removeGroupAdminTransactionData.getGroupName());
+		Group group = new Group(this.repository, removeGroupAdminTransactionData.getGroupId());
 		group.demoteFromAdmin(removeGroupAdminTransactionData);
 
 		// Save this transaction
@@ -141,7 +131,7 @@ public class RemoveGroupAdminTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert group adminship
-		Group group = new Group(this.repository, removeGroupAdminTransactionData.getGroupName());
+		Group group = new Group(this.repository, removeGroupAdminTransactionData.getGroupId());
 		group.undemoteFromAdmin(removeGroupAdminTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transaction/Transaction.java

@@ -58,7 +58,7 @@ public abstract class Transaction {
 		ADD_GROUP_ADMIN(24),
 		REMOVE_GROUP_ADMIN(25),
 		GROUP_BAN(26),
-		GROUP_UNBAN(27),
+		CANCEL_GROUP_BAN(27),
 		GROUP_KICK(28),
 		GROUP_INVITE(29),
 		CANCEL_GROUP_INVITE(30),
@@ -138,6 +138,7 @@ public abstract class Transaction {
 		BAN_EXISTS(58),
 		BAN_UNKNOWN(59),
 		BANNED_FROM_GROUP(60),
+		JOIN_REQUEST_EXISTS(61),
 		NOT_YET_RELEASED(1000);
 
 		public final int value;
@@ -252,8 +253,8 @@ public abstract class Transaction {
 			case GROUP_BAN:
 				return new GroupBanTransaction(repository, transactionData);
 
-			case GROUP_UNBAN:
+			case CANCEL_GROUP_BAN:
-				return new GroupUnbanTransaction(repository, transactionData);
+				return new CancelGroupBanTransaction(repository, transactionData);
 
 			case GROUP_KICK:
 				return new GroupKickTransaction(repository, transactionData);

src/main/java/org/qora/transaction/UpdateGroupTransaction.java

@@ -80,43 +80,39 @@ public class UpdateGroupTransaction extends Transaction {
 		if (!Crypto.isValidAddress(updateGroupTransactionData.getNewOwner()))
 			return ValidationResult.INVALID_ADDRESS;
 
-		// Check group name size bounds
-		int groupNameLength = Utf8.encodedLength(updateGroupTransactionData.getGroupName());
-		if (groupNameLength < 1 || groupNameLength > Group.MAX_NAME_SIZE)
-			return ValidationResult.INVALID_NAME_LENGTH;
-
 		// Check new description size bounds
 		int newDescriptionLength = Utf8.encodedLength(updateGroupTransactionData.getNewDescription());
 		if (newDescriptionLength < 1 || newDescriptionLength > Group.MAX_DESCRIPTION_SIZE)
 			return ValidationResult.INVALID_DESCRIPTION_LENGTH;
 
-		// Check group name is lowercase
+		GroupData groupData = this.repository.getGroupRepository().fromGroupId(updateGroupTransactionData.getGroupId());
-		if (!updateGroupTransactionData.getGroupName().equals(updateGroupTransactionData.getGroupName().toLowerCase()))
-			return ValidationResult.NAME_NOT_LOWER_CASE;
-
-		GroupData groupData = this.repository.getGroupRepository().fromGroupName(updateGroupTransactionData.getGroupName());
 
 		// Check group exists
 		if (groupData == null)
 			return ValidationResult.GROUP_DOES_NOT_EXIST;
 
-		// Check transaction's public key matches group's current owner
 		Account owner = getOwner();
+
+		// Check transaction's public key matches group's current owner
 		if (!owner.getAddress().equals(groupData.getOwner()))
 			return ValidationResult.INVALID_GROUP_OWNER;
 
+		Account newOwner = getNewOwner();
+
+		// Check new owner is not banned
+		if (this.repository.getGroupRepository().banExists(updateGroupTransactionData.getGroupId(), newOwner.getAddress()))
+			return ValidationResult.BANNED_FROM_GROUP;
+
 		// Check fee is positive
 		if (updateGroupTransactionData.getFee().compareTo(BigDecimal.ZERO) <= 0)
 			return ValidationResult.NEGATIVE_FEE;
 
 		// Check reference is correct
-		Account creator = getCreator();
+		if (!Arrays.equals(owner.getLastReference(), updateGroupTransactionData.getReference()))
-
-		if (!Arrays.equals(creator.getLastReference(), updateGroupTransactionData.getReference()))
 			return ValidationResult.INVALID_REFERENCE;
 
 		// Check creator has enough funds
-		if (creator.getConfirmedBalance(Asset.QORA).compareTo(updateGroupTransactionData.getFee()) < 0)
+		if (owner.getConfirmedBalance(Asset.QORA).compareTo(updateGroupTransactionData.getFee()) < 0)
 			return ValidationResult.NO_BALANCE;
 
 		return ValidationResult.OK;
@@ -125,7 +121,7 @@ public class UpdateGroupTransaction extends Transaction {
 	@Override
 	public void process() throws DataException {
 		// Update Group
-		Group group = new Group(this.repository, updateGroupTransactionData.getGroupName());
+		Group group = new Group(this.repository, updateGroupTransactionData.getGroupId());
 		group.updateGroup(updateGroupTransactionData);
 
 		// Save this transaction, now with updated "group reference" to previous transaction that updated group
@@ -142,7 +138,7 @@ public class UpdateGroupTransaction extends Transaction {
 	@Override
 	public void orphan() throws DataException {
 		// Revert Group update
-		Group group = new Group(this.repository, updateGroupTransactionData.getGroupName());
+		Group group = new Group(this.repository, updateGroupTransactionData.getGroupId());
 		group.unupdateGroup(updateGroupTransactionData);
 
 		// Delete this transaction itself

src/main/java/org/qora/transform/transaction/AddGroupAdminTransactionTransformer.java

@@ -9,11 +9,9 @@ import org.json.simple.JSONObject;
 import org.qora.account.PublicKeyAccount;
 import org.qora.data.transaction.AddGroupAdminTransactionData;
 import org.qora.data.transaction.TransactionData;
-import org.qora.group.Group;
 import org.qora.transform.TransformationException;
 import org.qora.utils.Serialization;
 
-import com.google.common.base.Utf8;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
@@ -22,10 +20,10 @@ public class AddGroupAdminTransactionTransformer extends TransactionTransformer
 
 	// Property lengths
 	private static final int OWNER_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int MEMBER_LENGTH = ADDRESS_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + NAME_SIZE_LENGTH + MEMBER_LENGTH;
+	private static final int TYPELESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + GROUPID_LENGTH + MEMBER_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -35,7 +33,7 @@ public class AddGroupAdminTransactionTransformer extends TransactionTransformer
 
 		byte[] ownerPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String member = Serialization.deserializeAddress(byteBuffer);
 
@@ -44,15 +42,11 @@ public class AddGroupAdminTransactionTransformer extends TransactionTransformer
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new AddGroupAdminTransactionData(ownerPublicKey, groupName, member, fee, timestamp, reference, signature);
+		return new AddGroupAdminTransactionData(ownerPublicKey, groupId, member, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
-		AddGroupAdminTransactionData addGroupAdminTransactionData = (AddGroupAdminTransactionData) transactionData;
+		return TYPE_LENGTH + TYPELESS_LENGTH;
-
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(addGroupAdminTransactionData.getGroupName());
-
-		return dataLength;
 	}
 
 	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
@@ -66,7 +60,7 @@ public class AddGroupAdminTransactionTransformer extends TransactionTransformer
 			bytes.write(addGroupAdminTransactionData.getReference());
 
 			bytes.write(addGroupAdminTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, addGroupAdminTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(addGroupAdminTransactionData.getGroupId()));
 			Serialization.serializeAddress(bytes, addGroupAdminTransactionData.getMember());
 
 			Serialization.serializeBigDecimal(bytes, addGroupAdminTransactionData.getFee());
@@ -92,7 +86,7 @@ public class AddGroupAdminTransactionTransformer extends TransactionTransformer
 			json.put("owner", PublicKeyAccount.getAddress(ownerPublicKey));
 			json.put("ownerPublicKey", HashCode.fromBytes(ownerPublicKey).toString());
 
-			json.put("groupName", addGroupAdminTransactionData.getGroupName());
+			json.put("groupId", addGroupAdminTransactionData.getGroupId());
 			json.put("member", addGroupAdminTransactionData.getMember());
 		} catch (ClassCastException e) {
 			throw new TransformationException(e);

src/main/java/org/qora/transform/transaction/CancelGroupBanTransactionTransformer.java

@@ -7,25 +7,23 @@ import java.nio.ByteBuffer;
 
 import org.json.simple.JSONObject;
 import org.qora.account.PublicKeyAccount;
-import org.qora.data.transaction.GroupUnbanTransactionData;
+import org.qora.data.transaction.CancelGroupBanTransactionData;
 import org.qora.data.transaction.TransactionData;
-import org.qora.group.Group;
 import org.qora.transform.TransformationException;
 import org.qora.utils.Serialization;
 
-import com.google.common.base.Utf8;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
 
-public class GroupUnbanTransactionTransformer extends TransactionTransformer {
+public class CancelGroupBanTransactionTransformer extends TransactionTransformer {
 
 	// Property lengths
 	private static final int ADMIN_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int MEMBER_LENGTH = ADDRESS_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + NAME_SIZE_LENGTH + MEMBER_LENGTH;
+	private static final int TYPELESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + GROUPID_LENGTH + MEMBER_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -35,7 +33,7 @@ public class GroupUnbanTransactionTransformer extends TransactionTransformer {
 
 		byte[] adminPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String member = Serialization.deserializeAddress(byteBuffer);
 
@@ -44,20 +42,16 @@ public class GroupUnbanTransactionTransformer extends TransactionTransformer {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new GroupUnbanTransactionData(adminPublicKey, groupName, member, fee, timestamp, reference, signature);
+		return new CancelGroupBanTransactionData(adminPublicKey, groupId, member, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
-		GroupUnbanTransactionData groupUnbanTransactionData = (GroupUnbanTransactionData) transactionData;
+		return TYPE_LENGTH + TYPELESS_LENGTH;
-
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(groupUnbanTransactionData.getGroupName());
-
-		return dataLength;
 	}
 
 	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
 		try {
-			GroupUnbanTransactionData groupUnbanTransactionData = (GroupUnbanTransactionData) transactionData;
+			CancelGroupBanTransactionData groupUnbanTransactionData = (CancelGroupBanTransactionData) transactionData;
 
 			ByteArrayOutputStream bytes = new ByteArrayOutputStream();
 
@@ -66,7 +60,7 @@ public class GroupUnbanTransactionTransformer extends TransactionTransformer {
 			bytes.write(groupUnbanTransactionData.getReference());
 
 			bytes.write(groupUnbanTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, groupUnbanTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(groupUnbanTransactionData.getGroupId()));
 			Serialization.serializeAddress(bytes, groupUnbanTransactionData.getMember());
 
 			Serialization.serializeBigDecimal(bytes, groupUnbanTransactionData.getFee());
@@ -85,14 +79,14 @@ public class GroupUnbanTransactionTransformer extends TransactionTransformer {
 		JSONObject json = TransactionTransformer.getBaseJSON(transactionData);
 
 		try {
-			GroupUnbanTransactionData groupUnbanTransactionData = (GroupUnbanTransactionData) transactionData;
+			CancelGroupBanTransactionData groupUnbanTransactionData = (CancelGroupBanTransactionData) transactionData;
 
 			byte[] adminPublicKey = groupUnbanTransactionData.getAdminPublicKey();
 
 			json.put("admin", PublicKeyAccount.getAddress(adminPublicKey));
 			json.put("adminPublicKey", HashCode.fromBytes(adminPublicKey).toString());
 
-			json.put("groupName", groupUnbanTransactionData.getGroupName());
+			json.put("groupId", groupUnbanTransactionData.getGroupId());
 			json.put("member", groupUnbanTransactionData.getMember());
 		} catch (ClassCastException e) {
 			throw new TransformationException(e);

src/main/java/org/qora/transform/transaction/CancelGroupInviteTransactionTransformer.java

@@ -9,11 +9,9 @@ import org.json.simple.JSONObject;
 import org.qora.account.PublicKeyAccount;
 import org.qora.data.transaction.CancelGroupInviteTransactionData;
 import org.qora.data.transaction.TransactionData;
-import org.qora.group.Group;
 import org.qora.transform.TransformationException;
 import org.qora.utils.Serialization;
 
-import com.google.common.base.Utf8;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
@@ -22,10 +20,10 @@ public class CancelGroupInviteTransactionTransformer extends TransactionTransfor
 
 	// Property lengths
 	private static final int ADMIN_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int INVITEE_LENGTH = ADDRESS_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + NAME_SIZE_LENGTH + INVITEE_LENGTH;
+	private static final int TYPELESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + GROUPID_LENGTH + INVITEE_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -35,7 +33,7 @@ public class CancelGroupInviteTransactionTransformer extends TransactionTransfor
 
 		byte[] adminPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String invitee = Serialization.deserializeAddress(byteBuffer);
 
@@ -44,15 +42,11 @@ public class CancelGroupInviteTransactionTransformer extends TransactionTransfor
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new CancelGroupInviteTransactionData(adminPublicKey, groupName, invitee, fee, timestamp, reference, signature);
+		return new CancelGroupInviteTransactionData(adminPublicKey, groupId, invitee, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
-		CancelGroupInviteTransactionData cancelGroupInviteTransactionData = (CancelGroupInviteTransactionData) transactionData;
+		return TYPE_LENGTH + TYPELESS_LENGTH;
-
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(cancelGroupInviteTransactionData.getGroupName());
-
-		return dataLength;
 	}
 
 	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
@@ -66,7 +60,7 @@ public class CancelGroupInviteTransactionTransformer extends TransactionTransfor
 			bytes.write(cancelGroupInviteTransactionData.getReference());
 
 			bytes.write(cancelGroupInviteTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, cancelGroupInviteTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(cancelGroupInviteTransactionData.getGroupId()));
 			Serialization.serializeAddress(bytes, cancelGroupInviteTransactionData.getInvitee());
 
 			Serialization.serializeBigDecimal(bytes, cancelGroupInviteTransactionData.getFee());
@@ -92,7 +86,7 @@ public class CancelGroupInviteTransactionTransformer extends TransactionTransfor
 			json.put("admin", PublicKeyAccount.getAddress(adminPublicKey));
 			json.put("adminPublicKey", HashCode.fromBytes(adminPublicKey).toString());
 
-			json.put("groupName", cancelGroupInviteTransactionData.getGroupName());
+			json.put("groupId", cancelGroupInviteTransactionData.getGroupId());
 			json.put("invitee", cancelGroupInviteTransactionData.getInvitee());
 		} catch (ClassCastException e) {
 			throw new TransformationException(e);

src/main/java/org/qora/transform/transaction/CreateGroupTransactionTransformer.java

@@ -27,7 +27,8 @@ public class CreateGroupTransactionTransformer extends TransactionTransformer {
 	private static final int DESCRIPTION_SIZE_LENGTH = INT_LENGTH;
 	private static final int IS_OPEN_LENGTH = BOOLEAN_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + CREATOR_LENGTH + OWNER_LENGTH + NAME_SIZE_LENGTH + DESCRIPTION_SIZE_LENGTH + IS_OPEN_LENGTH;
+	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + CREATOR_LENGTH + OWNER_LENGTH + NAME_SIZE_LENGTH + DESCRIPTION_SIZE_LENGTH
+			+ IS_OPEN_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -50,7 +51,7 @@ public class CreateGroupTransactionTransformer extends TransactionTransformer {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new CreateGroupTransactionData(creatorPublicKey, owner, groupName, description, isOpen, fee, timestamp, reference, signature);
+		return new CreateGroupTransactionData(creatorPublicKey, owner, groupName, description, isOpen, null, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {

src/main/java/org/qora/transform/transaction/GroupBanTransactionTransformer.java

@@ -22,12 +22,12 @@ public class GroupBanTransactionTransformer extends TransactionTransformer {
 
 	// Property lengths
 	private static final int ADMIN_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int MEMBER_LENGTH = ADDRESS_LENGTH;
 	private static final int REASON_SIZE_LENGTH = INT_LENGTH;
 	private static final int TTL_LENGTH = INT_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + NAME_SIZE_LENGTH + MEMBER_LENGTH + REASON_SIZE_LENGTH + TTL_LENGTH;
+	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + GROUPID_LENGTH + MEMBER_LENGTH + REASON_SIZE_LENGTH + TTL_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -37,7 +37,7 @@ public class GroupBanTransactionTransformer extends TransactionTransformer {
 
 		byte[] adminPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String offender = Serialization.deserializeAddress(byteBuffer);
 
@@ -50,14 +50,13 @@ public class GroupBanTransactionTransformer extends TransactionTransformer {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new GroupBanTransactionData(adminPublicKey, groupName, offender, reason, timeToLive, fee, timestamp, reference, signature);
+		return new GroupBanTransactionData(adminPublicKey, groupId, offender, reason, timeToLive, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
 		GroupBanTransactionData groupBanTransactionData = (GroupBanTransactionData) transactionData;
 
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(groupBanTransactionData.getGroupName())
+		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(groupBanTransactionData.getReason());
-				+ Utf8.encodedLength(groupBanTransactionData.getReason());
 
 		return dataLength;
 	}
@@ -73,7 +72,7 @@ public class GroupBanTransactionTransformer extends TransactionTransformer {
 			bytes.write(groupBanTransactionData.getReference());
 
 			bytes.write(groupBanTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, groupBanTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(groupBanTransactionData.getGroupId()));
 			Serialization.serializeAddress(bytes, groupBanTransactionData.getOffender());
 			Serialization.serializeSizedString(bytes, groupBanTransactionData.getReason());
 			bytes.write(Ints.toByteArray(groupBanTransactionData.getTimeToLive()));
@@ -101,7 +100,7 @@ public class GroupBanTransactionTransformer extends TransactionTransformer {
 			json.put("admin", PublicKeyAccount.getAddress(adminPublicKey));
 			json.put("adminPublicKey", HashCode.fromBytes(adminPublicKey).toString());
 
-			json.put("groupName", groupBanTransactionData.getGroupName());
+			json.put("groupId", groupBanTransactionData.getGroupId());
 			json.put("offender", groupBanTransactionData.getOffender());
 			json.put("reason", groupBanTransactionData.getReason());
 			json.put("timeToLive", groupBanTransactionData.getTimeToLive());

src/main/java/org/qora/transform/transaction/GroupInviteTransactionTransformer.java

@@ -9,11 +9,9 @@ import org.json.simple.JSONObject;
 import org.qora.account.PublicKeyAccount;
 import org.qora.data.transaction.GroupInviteTransactionData;
 import org.qora.data.transaction.TransactionData;
-import org.qora.group.Group;
 import org.qora.transform.TransformationException;
 import org.qora.utils.Serialization;
 
-import com.google.common.base.Utf8;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
@@ -22,11 +20,11 @@ public class GroupInviteTransactionTransformer extends TransactionTransformer {
 
 	// Property lengths
 	private static final int ADMIN_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int INVITEE_LENGTH = ADDRESS_LENGTH;
 	private static final int TTL_LENGTH = INT_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + NAME_SIZE_LENGTH + INVITEE_LENGTH + TTL_LENGTH;
+	private static final int TYPELESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + GROUPID_LENGTH + INVITEE_LENGTH + TTL_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -36,7 +34,7 @@ public class GroupInviteTransactionTransformer extends TransactionTransformer {
 
 		byte[] adminPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String invitee = Serialization.deserializeAddress(byteBuffer);
 
@@ -47,15 +45,11 @@ public class GroupInviteTransactionTransformer extends TransactionTransformer {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new GroupInviteTransactionData(adminPublicKey, groupName, invitee, timeToLive, fee, timestamp, reference, signature);
+		return new GroupInviteTransactionData(adminPublicKey, groupId, invitee, timeToLive, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
-		GroupInviteTransactionData groupInviteTransactionData = (GroupInviteTransactionData) transactionData;
+		return TYPE_LENGTH + TYPELESS_LENGTH;
-
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(groupInviteTransactionData.getGroupName());
-
-		return dataLength;
 	}
 
 	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
@@ -69,7 +63,7 @@ public class GroupInviteTransactionTransformer extends TransactionTransformer {
 			bytes.write(groupInviteTransactionData.getReference());
 
 			bytes.write(groupInviteTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, groupInviteTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(groupInviteTransactionData.getGroupId()));
 			Serialization.serializeAddress(bytes, groupInviteTransactionData.getInvitee());
 			bytes.write(Ints.toByteArray(groupInviteTransactionData.getTimeToLive()));
 
@@ -96,7 +90,7 @@ public class GroupInviteTransactionTransformer extends TransactionTransformer {
 			json.put("admin", PublicKeyAccount.getAddress(adminPublicKey));
 			json.put("adminPublicKey", HashCode.fromBytes(adminPublicKey).toString());
 
-			json.put("groupName", groupInviteTransactionData.getGroupName());
+			json.put("groupId", groupInviteTransactionData.getGroupId());
 			json.put("invitee", groupInviteTransactionData.getInvitee());
 			json.put("timeToLive", groupInviteTransactionData.getTimeToLive());
 		} catch (ClassCastException e) {

src/main/java/org/qora/transform/transaction/GroupKickTransactionTransformer.java

@@ -22,11 +22,11 @@ public class GroupKickTransactionTransformer extends TransactionTransformer {
 
 	// Property lengths
 	private static final int ADMIN_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int MEMBER_LENGTH = ADDRESS_LENGTH;
 	private static final int REASON_SIZE_LENGTH = INT_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + NAME_SIZE_LENGTH + MEMBER_LENGTH + REASON_SIZE_LENGTH;
+	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + ADMIN_LENGTH + GROUPID_LENGTH + MEMBER_LENGTH + REASON_SIZE_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -36,7 +36,7 @@ public class GroupKickTransactionTransformer extends TransactionTransformer {
 
 		byte[] adminPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String member = Serialization.deserializeAddress(byteBuffer);
 
@@ -47,14 +47,13 @@ public class GroupKickTransactionTransformer extends TransactionTransformer {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new GroupKickTransactionData(adminPublicKey, groupName, member, reason, fee, timestamp, reference, signature);
+		return new GroupKickTransactionData(adminPublicKey, groupId, member, reason, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
 		GroupKickTransactionData groupKickTransactionData = (GroupKickTransactionData) transactionData;
 
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(groupKickTransactionData.getGroupName())
+		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(groupKickTransactionData.getReason());
-				+ Utf8.encodedLength(groupKickTransactionData.getReason());
 
 		return dataLength;
 	}
@@ -70,7 +69,7 @@ public class GroupKickTransactionTransformer extends TransactionTransformer {
 			bytes.write(groupKickTransactionData.getReference());
 
 			bytes.write(groupKickTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, groupKickTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(groupKickTransactionData.getGroupId()));
 			Serialization.serializeAddress(bytes, groupKickTransactionData.getMember());
 			Serialization.serializeSizedString(bytes, groupKickTransactionData.getReason());
 
@@ -97,7 +96,7 @@ public class GroupKickTransactionTransformer extends TransactionTransformer {
 			json.put("admin", PublicKeyAccount.getAddress(adminPublicKey));
 			json.put("adminPublicKey", HashCode.fromBytes(adminPublicKey).toString());
 
-			json.put("groupName", groupKickTransactionData.getGroupName());
+			json.put("groupId", groupKickTransactionData.getGroupId());
 			json.put("member", groupKickTransactionData.getMember());
 			json.put("reason", groupKickTransactionData.getReason());
 		} catch (ClassCastException e) {

src/main/java/org/qora/transform/transaction/JoinGroupTransactionTransformer.java

@@ -9,11 +9,9 @@ import org.json.simple.JSONObject;
 import org.qora.account.PublicKeyAccount;
 import org.qora.data.transaction.JoinGroupTransactionData;
 import org.qora.data.transaction.TransactionData;
-import org.qora.group.Group;
 import org.qora.transform.TransformationException;
 import org.qora.utils.Serialization;
 
-import com.google.common.base.Utf8;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
@@ -22,9 +20,9 @@ public class JoinGroupTransactionTransformer extends TransactionTransformer {
 
 	// Property lengths
 	private static final int JOINER_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + JOINER_LENGTH + NAME_SIZE_LENGTH;
+	private static final int TYPELESS_LENGTH = BASE_TYPELESS_LENGTH + JOINER_LENGTH + GROUPID_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -34,22 +32,18 @@ public class JoinGroupTransactionTransformer extends TransactionTransformer {
 
 		byte[] joinerPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		BigDecimal fee = Serialization.deserializeBigDecimal(byteBuffer);
 
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new JoinGroupTransactionData(joinerPublicKey, groupName, fee, timestamp, reference, signature);
+		return new JoinGroupTransactionData(joinerPublicKey, groupId, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
-		JoinGroupTransactionData joinGroupTransactionData = (JoinGroupTransactionData) transactionData;
+		return TYPE_LENGTH + TYPELESS_LENGTH;
-
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(joinGroupTransactionData.getGroupName());
-
-		return dataLength;
 	}
 
 	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
@@ -63,7 +57,7 @@ public class JoinGroupTransactionTransformer extends TransactionTransformer {
 			bytes.write(joinGroupTransactionData.getReference());
 
 			bytes.write(joinGroupTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, joinGroupTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(joinGroupTransactionData.getGroupId()));
 
 			Serialization.serializeBigDecimal(bytes, joinGroupTransactionData.getFee());
 
@@ -88,7 +82,7 @@ public class JoinGroupTransactionTransformer extends TransactionTransformer {
 			json.put("joiner", PublicKeyAccount.getAddress(joinerPublicKey));
 			json.put("joinerPublicKey", HashCode.fromBytes(joinerPublicKey).toString());
 
-			json.put("groupName", joinGroupTransactionData.getGroupName());
+			json.put("groupId", joinGroupTransactionData.getGroupId());
 		} catch (ClassCastException e) {
 			throw new TransformationException(e);
 		}

src/main/java/org/qora/transform/transaction/LeaveGroupTransactionTransformer.java

@@ -9,11 +9,9 @@ import org.json.simple.JSONObject;
 import org.qora.account.PublicKeyAccount;
 import org.qora.data.transaction.LeaveGroupTransactionData;
 import org.qora.data.transaction.TransactionData;
-import org.qora.group.Group;
 import org.qora.transform.TransformationException;
 import org.qora.utils.Serialization;
 
-import com.google.common.base.Utf8;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
@@ -22,9 +20,9 @@ public class LeaveGroupTransactionTransformer extends TransactionTransformer {
 
 	// Property lengths
 	private static final int JOINER_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + JOINER_LENGTH + NAME_SIZE_LENGTH;
+	private static final int TYPELESS_LENGTH = BASE_TYPELESS_LENGTH + JOINER_LENGTH + GROUPID_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -34,22 +32,18 @@ public class LeaveGroupTransactionTransformer extends TransactionTransformer {
 
 		byte[] leaverPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		BigDecimal fee = Serialization.deserializeBigDecimal(byteBuffer);
 
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new LeaveGroupTransactionData(leaverPublicKey, groupName, fee, timestamp, reference, signature);
+		return new LeaveGroupTransactionData(leaverPublicKey, groupId, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
-		LeaveGroupTransactionData leaveGroupTransactionData = (LeaveGroupTransactionData) transactionData;
+		return TYPE_LENGTH + TYPELESS_LENGTH;
-
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(leaveGroupTransactionData.getGroupName());
-
-		return dataLength;
 	}
 
 	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
@@ -63,7 +57,7 @@ public class LeaveGroupTransactionTransformer extends TransactionTransformer {
 			bytes.write(leaveGroupTransactionData.getReference());
 
 			bytes.write(leaveGroupTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, leaveGroupTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(leaveGroupTransactionData.getGroupId()));
 
 			Serialization.serializeBigDecimal(bytes, leaveGroupTransactionData.getFee());
 
@@ -88,7 +82,7 @@ public class LeaveGroupTransactionTransformer extends TransactionTransformer {
 			json.put("leaver", PublicKeyAccount.getAddress(leaverPublicKey));
 			json.put("leaverPublicKey", HashCode.fromBytes(leaverPublicKey).toString());
 
-			json.put("groupName", leaveGroupTransactionData.getGroupName());
+			json.put("groupId", leaveGroupTransactionData.getGroupId());
 		} catch (ClassCastException e) {
 			throw new TransformationException(e);
 		}

src/main/java/org/qora/transform/transaction/RemoveGroupAdminTransactionTransformer.java

@@ -9,11 +9,9 @@ import org.json.simple.JSONObject;
 import org.qora.account.PublicKeyAccount;
 import org.qora.data.transaction.RemoveGroupAdminTransactionData;
 import org.qora.data.transaction.TransactionData;
-import org.qora.group.Group;
 import org.qora.transform.TransformationException;
 import org.qora.utils.Serialization;
 
-import com.google.common.base.Utf8;
 import com.google.common.hash.HashCode;
 import com.google.common.primitives.Ints;
 import com.google.common.primitives.Longs;
@@ -22,10 +20,10 @@ public class RemoveGroupAdminTransactionTransformer extends TransactionTransform
 
 	// Property lengths
 	private static final int OWNER_LENGTH = PUBLIC_KEY_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int MEMBER_LENGTH = ADDRESS_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + NAME_SIZE_LENGTH + MEMBER_LENGTH;
+	private static final int TYPELESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + GROUPID_LENGTH + MEMBER_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -35,7 +33,7 @@ public class RemoveGroupAdminTransactionTransformer extends TransactionTransform
 
 		byte[] ownerPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String admin = Serialization.deserializeAddress(byteBuffer);
 
@@ -44,15 +42,11 @@ public class RemoveGroupAdminTransactionTransformer extends TransactionTransform
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new RemoveGroupAdminTransactionData(ownerPublicKey, groupName, admin, fee, timestamp, reference, signature);
+		return new RemoveGroupAdminTransactionData(ownerPublicKey, groupId, admin, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
-		RemoveGroupAdminTransactionData removeGroupAdminTransactionData = (RemoveGroupAdminTransactionData) transactionData;
+		return TYPE_LENGTH + TYPELESS_LENGTH;
-
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(removeGroupAdminTransactionData.getGroupName());
-
-		return dataLength;
 	}
 
 	public static byte[] toBytes(TransactionData transactionData) throws TransformationException {
@@ -66,7 +60,7 @@ public class RemoveGroupAdminTransactionTransformer extends TransactionTransform
 			bytes.write(removeGroupAdminTransactionData.getReference());
 
 			bytes.write(removeGroupAdminTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, removeGroupAdminTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(removeGroupAdminTransactionData.getGroupId()));
 			Serialization.serializeAddress(bytes, removeGroupAdminTransactionData.getAdmin());
 
 			Serialization.serializeBigDecimal(bytes, removeGroupAdminTransactionData.getFee());
@@ -92,7 +86,7 @@ public class RemoveGroupAdminTransactionTransformer extends TransactionTransform
 			json.put("owner", PublicKeyAccount.getAddress(ownerPublicKey));
 			json.put("ownerPublicKey", HashCode.fromBytes(ownerPublicKey).toString());
 
-			json.put("groupName", removeGroupAdminTransactionData.getGroupName());
+			json.put("groupId", removeGroupAdminTransactionData.getGroupId());
 			json.put("admin", removeGroupAdminTransactionData.getAdmin());
 		} catch (ClassCastException e) {
 			throw new TransformationException(e);

src/main/java/org/qora/transform/transaction/TransactionTransformer.java

@@ -109,8 +109,8 @@ public class TransactionTransformer extends Transformer {
 				case GROUP_BAN:
 					return GroupBanTransactionTransformer.fromByteBuffer(byteBuffer);
 
-				case GROUP_UNBAN:
+				case CANCEL_GROUP_BAN:
-					return GroupUnbanTransactionTransformer.fromByteBuffer(byteBuffer);
+					return CancelGroupBanTransactionTransformer.fromByteBuffer(byteBuffer);
 
 				case GROUP_KICK:
 					return GroupKickTransactionTransformer.fromByteBuffer(byteBuffer);
@@ -203,8 +203,8 @@ public class TransactionTransformer extends Transformer {
 			case GROUP_BAN:
 				return GroupBanTransactionTransformer.getDataLength(transactionData);
 
-			case GROUP_UNBAN:
+			case CANCEL_GROUP_BAN:
-				return GroupUnbanTransactionTransformer.getDataLength(transactionData);
+				return CancelGroupBanTransactionTransformer.getDataLength(transactionData);
 
 			case GROUP_KICK:
 				return GroupKickTransactionTransformer.getDataLength(transactionData);
@@ -294,8 +294,8 @@ public class TransactionTransformer extends Transformer {
 			case GROUP_BAN:
 				return GroupBanTransactionTransformer.toBytes(transactionData);
 
-			case GROUP_UNBAN:
+			case CANCEL_GROUP_BAN:
-				return GroupUnbanTransactionTransformer.toBytes(transactionData);
+				return CancelGroupBanTransactionTransformer.toBytes(transactionData);
 
 			case GROUP_KICK:
 				return GroupKickTransactionTransformer.toBytes(transactionData);
@@ -394,8 +394,8 @@ public class TransactionTransformer extends Transformer {
 			case GROUP_BAN:
 				return GroupBanTransactionTransformer.toBytesForSigningImpl(transactionData);
 
-			case GROUP_UNBAN:
+			case CANCEL_GROUP_BAN:
-				return GroupUnbanTransactionTransformer.toBytesForSigningImpl(transactionData);
+				return CancelGroupBanTransactionTransformer.toBytesForSigningImpl(transactionData);
 
 			case GROUP_KICK:
 				return GroupKickTransactionTransformer.toBytesForSigningImpl(transactionData);
@@ -506,8 +506,8 @@ public class TransactionTransformer extends Transformer {
 			case GROUP_BAN:
 				return GroupBanTransactionTransformer.toJSON(transactionData);
 
-			case GROUP_UNBAN:
+			case CANCEL_GROUP_BAN:
-				return GroupUnbanTransactionTransformer.toJSON(transactionData);
+				return CancelGroupBanTransactionTransformer.toJSON(transactionData);
 
 			case GROUP_KICK:
 				return GroupKickTransactionTransformer.toJSON(transactionData);

src/main/java/org/qora/transform/transaction/UpdateGroupTransactionTransformer.java

@@ -22,12 +22,13 @@ public class UpdateGroupTransactionTransformer extends TransactionTransformer {
 
 	// Property lengths
 	private static final int OWNER_LENGTH = PUBLIC_KEY_LENGTH;
+	private static final int GROUPID_LENGTH = INT_LENGTH;
 	private static final int NEW_OWNER_LENGTH = ADDRESS_LENGTH;
-	private static final int NAME_SIZE_LENGTH = INT_LENGTH;
 	private static final int NEW_DESCRIPTION_SIZE_LENGTH = INT_LENGTH;
 	private static final int NEW_IS_OPEN_LENGTH = BOOLEAN_LENGTH;
 
-	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + NEW_OWNER_LENGTH + NAME_SIZE_LENGTH + NEW_DESCRIPTION_SIZE_LENGTH + NEW_IS_OPEN_LENGTH;
+	private static final int TYPELESS_DATALESS_LENGTH = BASE_TYPELESS_LENGTH + OWNER_LENGTH + GROUPID_LENGTH + NEW_OWNER_LENGTH + NEW_DESCRIPTION_SIZE_LENGTH
+			+ NEW_IS_OPEN_LENGTH;
 
 	static TransactionData fromByteBuffer(ByteBuffer byteBuffer) throws TransformationException {
 		long timestamp = byteBuffer.getLong();
@@ -37,7 +38,7 @@ public class UpdateGroupTransactionTransformer extends TransactionTransformer {
 
 		byte[] ownerPublicKey = Serialization.deserializePublicKey(byteBuffer);
 
-		String groupName = Serialization.deserializeSizedString(byteBuffer, Group.MAX_NAME_SIZE);
+		int groupId = byteBuffer.getInt();
 
 		String newOwner = Serialization.deserializeAddress(byteBuffer);
 
@@ -50,14 +51,13 @@ public class UpdateGroupTransactionTransformer extends TransactionTransformer {
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
-		return new UpdateGroupTransactionData(ownerPublicKey, groupName, newOwner, newDescription, newIsOpen, fee, timestamp, reference, signature);
+		return new UpdateGroupTransactionData(ownerPublicKey, groupId, newOwner, newDescription, newIsOpen, fee, timestamp, reference, signature);
 	}
 
 	public static int getDataLength(TransactionData transactionData) throws TransformationException {
 		UpdateGroupTransactionData updateGroupTransactionData = (UpdateGroupTransactionData) transactionData;
 
-		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(updateGroupTransactionData.getGroupName())
+		int dataLength = TYPE_LENGTH + TYPELESS_DATALESS_LENGTH + Utf8.encodedLength(updateGroupTransactionData.getNewDescription());
-				+ Utf8.encodedLength(updateGroupTransactionData.getNewDescription());
 
 		return dataLength;
 	}
@@ -73,7 +73,7 @@ public class UpdateGroupTransactionTransformer extends TransactionTransformer {
 			bytes.write(updateGroupTransactionData.getReference());
 
 			bytes.write(updateGroupTransactionData.getCreatorPublicKey());
-			Serialization.serializeSizedString(bytes, updateGroupTransactionData.getGroupName());
+			bytes.write(Ints.toByteArray(updateGroupTransactionData.getGroupId()));
 
 			Serialization.serializeAddress(bytes, updateGroupTransactionData.getNewOwner());
 			Serialization.serializeSizedString(bytes, updateGroupTransactionData.getNewDescription());
@@ -103,7 +103,7 @@ public class UpdateGroupTransactionTransformer extends TransactionTransformer {
 			json.put("owner", PublicKeyAccount.getAddress(ownerPublicKey));
 			json.put("ownerPublicKey", HashCode.fromBytes(ownerPublicKey).toString());
 
-			json.put("groupName", updateGroupTransactionData.getGroupName());
+			json.put("groupId", updateGroupTransactionData.getGroupId());
 			json.put("newOwner", updateGroupTransactionData.getNewOwner());
 			json.put("newDescription", updateGroupTransactionData.getNewDescription());
 			json.put("newIsOpen", updateGroupTransactionData.getNewIsOpen());