Disable archiving and pruning if the AtStatesHeightIndex is missing, and log it so that the user knows they should bootstrap or resync.

src/main/java/org/qortal/controller/repository/BlockArchiver.java

@@ -27,6 +27,13 @@ public class BlockArchiver implements Runnable {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			int startHeight = repository.getBlockArchiveRepository().getBlockArchiveHeight();
 
+			// Don't attempt to archive if we have no ATStatesHeightIndex, as it will be too slow
+			boolean hasAtStatesHeightIndex = repository.getATRepository().hasAtStatesHeightIndex();
+			if (!hasAtStatesHeightIndex) {
+				LOGGER.info("Unable to start block archiver due to missing ATStatesHeightIndex. Bootstrapping is recommended.");
+				return;
+			}
+
 			// Don't even start building until initial rush has ended
 			Thread.sleep(INITIAL_SLEEP_PERIOD);
 

src/main/java/org/qortal/controller/repository/BlockPruner.java

@@ -34,6 +34,13 @@ public class BlockPruner implements Runnable {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			int pruneStartHeight = repository.getBlockRepository().getBlockPruneHeight();
 
+			// Don't attempt to prune if we have no ATStatesHeightIndex, as it will be too slow
+			boolean hasAtStatesHeightIndex = repository.getATRepository().hasAtStatesHeightIndex();
+			if (!hasAtStatesHeightIndex) {
+				LOGGER.info("Unable to start block pruner due to missing ATStatesHeightIndex. Bootstrapping is recommended.");
+				return;
+			}
+
 			while (!Controller.isStopping()) {
 				repository.discardChanges();
 

src/main/java/org/qortal/repository/ATRepository.java

@@ -1,5 +1,7 @@
 package org.qortal.repository;
 
+import java.sql.ResultSet;
+import java.sql.SQLException;
 import java.util.List;
 import java.util.Set;
 
@@ -146,6 +148,10 @@ public interface ATRepository {
 	public int pruneAtStates(int minHeight, int maxHeight) throws DataException;
 
 
+	/** Checks for the presence of the ATStatesHeightIndex in repository */
+	public boolean hasAtStatesHeightIndex() throws DataException;
+
+
 	/**
 	 * Save ATStateData into repository.
 	 * <p>

src/main/java/org/qortal/repository/RepositoryManager.java

@@ -61,11 +61,16 @@ public abstract class RepositoryManager {
 	public static boolean archive() {
 		// Bulk archive the database the first time we use archive mode
 		if (Settings.getInstance().isArchiveEnabled()) {
+			if (RepositoryManager.canArchiveOrPrune()) {
 				try {
 					return HSQLDBDatabaseArchiving.buildBlockArchive();
 
 				} catch (DataException e) {
-				LOGGER.info("Unable to bulk prune AT states. The database may have been left in an inconsistent state.");
+					LOGGER.info("Unable to build block archive. The database may have been left in an inconsistent state.");
+				}
+			}
+			else {
+				LOGGER.info("Unable to build block archive due to missing ATStatesHeightIndex. Bootstrapping is recommended.");
 			}
 		}
 		return false;
@@ -75,6 +80,7 @@ public abstract class RepositoryManager {
 		// Bulk prune the database the first time we use pruning mode
 		if (Settings.getInstance().isPruningEnabled() ||
 			Settings.getInstance().isArchiveEnabled()) {
+			if (RepositoryManager.canArchiveOrPrune()) {
 				try {
 					boolean prunedATStates = HSQLDBDatabasePruning.pruneATStates();
 					boolean prunedBlocks = HSQLDBDatabasePruning.pruneBlocks();
@@ -89,6 +95,10 @@ public abstract class RepositoryManager {
 					LOGGER.info("Unable to bulk prune AT states. The database may have been left in an inconsistent state.");
 				}
 			}
+			else {
+				LOGGER.info("Unable to prune blocks due to missing ATStatesHeightIndex. Bootstrapping is recommended.");
+			}
+		}
 		return false;
 	}
 
@@ -118,4 +128,12 @@ public abstract class RepositoryManager {
 		return SQLException.class.isInstance(cause) && repositoryFactory.isDeadlockException((SQLException) cause);
 	}
 
+	public static boolean canArchiveOrPrune() {
+		try (final Repository repository = getRepository()) {
+			return repository.getATRepository().hasAtStatesHeightIndex();
+		} catch (DataException e) {
+			return false;
+		}
+	}
+
 }

src/main/java/org/qortal/repository/hsqldb/HSQLDBATRepository.java

@@ -798,6 +798,19 @@ public class HSQLDBATRepository implements ATRepository {
 	}
 
 
+	@Override
+	public boolean hasAtStatesHeightIndex() throws DataException {
+		String sql = "SELECT INDEX_NAME FROM INFORMATION_SCHEMA.SYSTEM_INDEXINFO where INDEX_NAME='ATSTATESHEIGHTINDEX'";
+
+		try (ResultSet resultSet = this.repository.checkedExecute(sql)) {
+			return resultSet != null;
+
+		} catch (SQLException e) {
+			throw new DataException("Unable to check for ATStatesHeightIndex in repository", e);
+		}
+	}
+
+
 	@Override
 	public void save(ATStateData atStateData) throws DataException {
 		// We shouldn't ever save partial ATStateData

src/test/java/org/qortal/test/BlockArchiveTests.java

@@ -17,6 +17,7 @@ import org.qortal.data.transaction.DeployAtTransactionData;
 import org.qortal.data.transaction.TransactionData;
 import org.qortal.group.Group;
 import org.qortal.repository.*;
+import org.qortal.repository.hsqldb.HSQLDBRepository;
 import org.qortal.settings.Settings;
 import org.qortal.test.common.AtUtils;
 import org.qortal.test.common.BlockUtils;
@@ -33,6 +34,7 @@ import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -487,6 +489,29 @@ public class BlockArchiveTests extends Common {
 	}
 
 
+	/**
+	 * Many nodes are missing an ATStatesHeightIndex due to an earlier bug
+	 * In these cases we disable archiving and pruning as this index is a
+	 * very essential component in these processes.
+	 */
+	@Test
+	public void testMissingAtStatesHeightIndex() throws DataException, SQLException {
+		try (final HSQLDBRepository repository = (HSQLDBRepository) RepositoryManager.getRepository()) {
+
+			// Firstly check that we're able to prune or archive when the index exists
+			assertTrue(repository.getATRepository().hasAtStatesHeightIndex());
+			assertTrue(RepositoryManager.canArchiveOrPrune());
+
+			// Delete the index
+			repository.prepareStatement("DROP INDEX ATSTATESHEIGHTINDEX").execute();
+
+			// Ensure check that we're unable to prune or archive when the index doesn't exist
+			assertFalse(repository.getATRepository().hasAtStatesHeightIndex());
+			assertFalse(RepositoryManager.canArchiveOrPrune());
+		}
+	}
+
+
 	private void deleteArchiveDirectory() {
 		// Delete archive directory if exists
 		Path archivePath = Paths.get(Settings.getInstance().getRepositoryPath(), "archive").toAbsolutePath();