Remove length limitations for table renames

src/backend/distributed/commands/alter_table.c

@@ -49,6 +49,8 @@
 #include "distributed/multi_logical_planner.h"
 #include "distributed/multi_partitioning_utils.h"
 #include "distributed/reference_table_utils.h"
+#include "distributed/relation_access_tracking.h"
+#include "distributed/shard_utils.h"
 #include "distributed/worker_protocol.h"
 #include "distributed/worker_transaction.h"
 #include "executor/spi.h"
@@ -175,6 +177,8 @@ static TableConversionReturn * AlterDistributedTable(TableConversionParameters *
 static TableConversionReturn * AlterTableSetAccessMethod(
 	TableConversionParameters *params);
 static TableConversionReturn * ConvertTable(TableConversionState *con);
+static bool SwitchToSequentialAndLocalExecutionIfShardNameTooLong(char *relationName,
+																  char *longestShardName);
 static void EnsureTableNotReferencing(Oid relationId, char conversionType);
 static void EnsureTableNotReferenced(Oid relationId, char conversionType);
 static void EnsureTableNotForeign(Oid relationId);
@@ -511,6 +515,10 @@ ConvertTable(TableConversionState *con)
 	bool oldEnableLocalReferenceForeignKeys = EnableLocalReferenceForeignKeys;
 	SetLocalEnableLocalReferenceForeignKeys(false);
 
+	/* switch to sequential execution if shard names will be too long */
+	SwitchToSequentialAndLocalExecutionIfRelationNameTooLong(con->relationId,
+															 con->relationName);
+
 	if (con->conversionType == UNDISTRIBUTE_TABLE && con->cascadeViaForeignKeys &&
 		(TableReferencing(con->relationId) || TableReferenced(con->relationId)))
 	{
@@ -1572,3 +1580,104 @@ ExecuteQueryViaSPI(char *query, int SPIOK)
 		ereport(ERROR, (errmsg("could not finish SPI connection")));
 	}
 }
+
+
+/*
+ * SwitchToSequentialAndLocalExecutionIfRelationNameTooLong generates the longest shard name
+ * on the shards of a distributed table, and if exceeds the limit switches to sequential and
+ * local execution to prevent self-deadlocks.
+ *
+ * In case of a RENAME, the relation name parameter should store the new table name, so
+ * that the function can generate shard names of the renamed relations
+ */
+void
+SwitchToSequentialAndLocalExecutionIfRelationNameTooLong(Oid relationId,
+														 char *finalRelationName)
+{
+	if (!IsCitusTable(relationId))
+	{
+		return;
+	}
+
+	if (ShardIntervalCount(relationId) == 0)
+	{
+		/*
+		 * Relation has no shards, so we cannot run into "long shard relation
+		 * name" issue.
+		 */
+		return;
+	}
+
+	char *longestShardName = GetLongestShardName(relationId, finalRelationName);
+	bool switchedToSequentialAndLocalExecution =
+		SwitchToSequentialAndLocalExecutionIfShardNameTooLong(finalRelationName,
+															  longestShardName);
+
+	if (switchedToSequentialAndLocalExecution)
+	{
+		return;
+	}
+
+	if (PartitionedTable(relationId))
+	{
+		Oid longestNamePartitionId = PartitionWithLongestNameRelationId(relationId);
+		if (!OidIsValid(longestNamePartitionId))
+		{
+			/* no partitions have been created yet */
+			return;
+		}
+
+		char *longestPartitionName = get_rel_name(longestNamePartitionId);
+		char *longestPartitionShardName = GetLongestShardName(longestNamePartitionId,
+															  longestPartitionName);
+
+		SwitchToSequentialAndLocalExecutionIfShardNameTooLong(longestPartitionName,
+															  longestPartitionShardName);
+	}
+}
+
+
+/*
+ * SwitchToSequentialAndLocalExecutionIfShardNameTooLong switches to sequential and local
+ * execution if the shard name is too long.
+ *
+ * returns true if switched to sequential and local execution.
+ */
+static bool
+SwitchToSequentialAndLocalExecutionIfShardNameTooLong(char *relationName,
+													  char *longestShardName)
+{
+	if (strlen(longestShardName) >= NAMEDATALEN - 1)
+	{
+		if (ParallelQueryExecutedInTransaction())
+		{
+			/*
+			 * If there has already been a parallel query executed, the sequential mode
+			 * would still use the already opened parallel connections to the workers,
+			 * thus contradicting our purpose of using sequential mode.
+			 */
+			ereport(ERROR, (errmsg(
+								"Shard name (%s) for table (%s) is too long and could "
+								"lead to deadlocks when executed in a transaction "
+								"block after a parallel query", longestShardName,
+								relationName),
+							errhint("Try re-running the transaction with "
+									"\"SET LOCAL citus.multi_shard_modify_mode TO "
+									"\'sequential\';\"")));
+		}
+		else
+		{
+			elog(DEBUG1, "the name of the shard (%s) for relation (%s) is too long, "
+						 "switching to sequential and local execution mode to prevent "
+						 "self deadlocks",
+				 longestShardName, relationName);
+
+			SetLocalMultiShardModifyModeToSequential();
+			SetLocalExecutionStatus(LOCAL_EXECUTION_REQUIRED);
+
+			return true;
+		}
+	}
+
+	return false;
+}

src/backend/distributed/commands/index.c

@@ -410,15 +410,16 @@ static char *
 GenerateLongestShardPartitionIndexName(IndexStmt *createIndexStatement)
 {
 	Oid relationId = CreateIndexStmtGetRelationId(createIndexStatement);
-	char *longestPartitionName = LongestPartitionName(relationId);
+	Oid longestNamePartitionId = PartitionWithLongestNameRelationId(relationId);
-	if (longestPartitionName == NULL)
+	if (!OidIsValid(longestNamePartitionId))
 	{
 		/* no partitions have been created yet */
 		return NULL;
 	}
 
-	char *longestPartitionShardName = pstrdup(longestPartitionName);
+	char *longestPartitionShardName = get_rel_name(longestNamePartitionId);
-	ShardInterval *shardInterval = LoadShardIntervalWithLongestShardName(relationId);
+	ShardInterval *shardInterval = LoadShardIntervalWithLongestShardName(
+		longestNamePartitionId);
 	AppendShardIdToName(&longestPartitionShardName, shardInterval->shardId);
 
 	IndexStmt *createLongestShardIndexStmt = copyObject(createIndexStatement);

src/backend/distributed/commands/rename.c

@@ -109,6 +109,13 @@ PreprocessRenameStmt(Node *node, const char *renameCommand,
 	 */
 	ErrorIfUnsupportedRenameStmt(renameStmt);
 
+	if (renameStmt->renameType == OBJECT_TABLE ||
+		renameStmt->renameType == OBJECT_FOREIGN_TABLE)
+	{
+		SwitchToSequentialAndLocalExecutionIfRelationNameTooLong(tableRelationId,
+																 renameStmt->newname);
+	}
+
 	DDLJob *ddlJob = palloc0(sizeof(DDLJob));
 	ddlJob->targetRelationId = tableRelationId;
 	ddlJob->concurrentIndexCmd = false;

src/backend/distributed/relay/relay_event_utility.c

@@ -556,30 +556,6 @@ RelayEventExtendNames(Node *parseTree, char *schemaName, uint64 shardId)
 
 				AppendShardIdToName(oldRelationName, shardId);
 				AppendShardIdToName(newRelationName, shardId);
-
-				/*
-				 * PostgreSQL creates array types for each ordinary table, with
-				 * the same name plus a prefix of '_'.
-				 *
-				 * ALTER TABLE ... RENAME TO ... also renames the underlying
-				 * array type, and the DDL is run in parallel connections over
-				 * all the placements and shards at once. Concurrent access
-				 * here deadlocks.
-				 *
-				 * Let's provide an easier to understand error message here
-				 * than the deadlock one.
-				 *
-				 * See also https://github.com/citusdata/citus/issues/1664
-				 */
-				int newRelationNameLength = strlen(*newRelationName);
-				if (newRelationNameLength >= (NAMEDATALEN - 1))
-				{
-					ereport(ERROR,
-							(errcode(ERRCODE_NAME_TOO_LONG),
-							 errmsg(
-								 "shard name %s exceeds %d characters",
-								 *newRelationName, NAMEDATALEN - 1)));
-				}
 			}
 			else if (objectType == OBJECT_COLUMN)
 			{

src/backend/distributed/utils/multi_partitioning_utils.c

@@ -548,13 +548,14 @@ PartitionParentOid(Oid partitionOid)
 
 
 /*
- * LongestPartitionName is a uitility function that returns the partition
+ * PartitionWithLongestNameRelationId is a utility function that returns the
- * name which is the longest in terms of number of characters.
+ * oid of the partition table that has the longest name in terms of number of
+ * characters.
  */
-char *
+Oid
-LongestPartitionName(Oid parentRelationId)
+PartitionWithLongestNameRelationId(Oid parentRelationId)
 {
-	char *longestName = NULL;
+	Oid longestNamePartitionId = InvalidOid;
 	int longestNameLength = 0;
 	List *partitionList = PartitionList(parentRelationId);
 
@@ -565,12 +566,12 @@ LongestPartitionName(Oid parentRelationId)
 		int partitionNameLength = strnlen(partitionName, NAMEDATALEN);
 		if (partitionNameLength > longestNameLength)
 		{
-			longestName = partitionName;
+			longestNamePartitionId = partitionRelationId;
 			longestNameLength = partitionNameLength;
 		}
 	}
 
-	return longestName;
+	return longestNamePartitionId;
 }
 
 

src/backend/distributed/utils/shard_utils.c

@@ -12,6 +12,7 @@
 #include "postgres.h"
 
 #include "utils/lsyscache.h"
+#include "distributed/metadata_utility.h"
 #include "distributed/relay_utility.h"
 #include "distributed/shard_utils.h"
 
@@ -36,3 +37,21 @@ GetTableLocalShardOid(Oid citusTableOid, uint64 shardId)
 
 	return shardRelationOid;
 }
+
+
+/*
+ * GetLongestShardName is a utility function that returns the name of the shard of a
+ * table that has the longest name in terms of number of characters.
+ *
+ * Both the Oid and name of the table are required so we can create longest shard names
+ * after a RENAME.
+ */
+char *
+GetLongestShardName(Oid citusTableOid, char *finalRelationName)
+{
+	char *longestShardName = pstrdup(finalRelationName);
+	ShardInterval *shardInterval = LoadShardIntervalWithLongestShardName(citusTableOid);
+	AppendShardIdToName(&longestShardName, shardInterval->shardId);
+
+	return longestShardName;
+}

src/include/distributed/commands.h

@@ -24,6 +24,10 @@
 /* controlled via GUC, should be accessed via EnableLocalReferenceForeignKeys() */
 extern bool EnableLocalReferenceForeignKeys;
 
+extern void SwitchToSequentialAndLocalExecutionIfRelationNameTooLong(Oid relationId,
+																	 char *
+																	 finalRelationName);
+
 
 /*
  * DistributeObjectOps specifies handlers for node/object type pairs.

src/include/distributed/multi_partitioning_utils.h

@@ -19,7 +19,7 @@ extern bool PartitionTableNoLock(Oid relationId);
 extern bool IsChildTable(Oid relationId);
 extern bool IsParentTable(Oid relationId);
 extern Oid PartitionParentOid(Oid partitionOid);
-extern char * LongestPartitionName(Oid parentRelationId);
+extern Oid PartitionWithLongestNameRelationId(Oid parentRelationId);
 extern List * PartitionList(Oid parentRelationId);
 extern char * GenerateDetachPartitionCommand(Oid partitionTableId);
 extern char * GenerateAttachShardPartitionCommand(ShardInterval *shardInterval);

src/include/distributed/shard_utils.h

@@ -14,5 +14,6 @@
 #include "postgres.h"
 
 extern Oid GetTableLocalShardOid(Oid citusTableOid, uint64 shardId);
+extern char * GetLongestShardName(Oid citusTableOid, char *finalRelationName);
 
 #endif /* SHARD_UTILS_H */

src/test/regress/expected/alter_distributed_table.out

@@ -848,6 +848,7 @@ SELECT create_distributed_table('abcde_01234567890123456789012345678901234567890
 (1 row)
 
 SELECT alter_distributed_table('abcde_0123456789012345678901234567890123456789012345678901234567890123456789', distribution_column := 'y');
+DEBUG:  the name of the shard (abcde_01234567890123456789012345678901234567890_f7ff6612_xxxxxx) for relation (abcde_012345678901234567890123456789012345678901234567890123456) is too long, switching to sequential and local execution mode to prevent self deadlocks
 NOTICE:  creating a new table for alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
 NOTICE:  Moving the data of alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
 DEBUG:  cannot perform distributed INSERT INTO ... SELECT because the partition columns in the source table and subquery do not match
@@ -858,9 +859,13 @@ CONTEXT:  SQL statement "INSERT INTO alter_distributed_table.abcde_0123456789012
 NOTICE:  Dropping the old alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
 CONTEXT:  SQL statement "DROP TABLE alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456 CASCADE"
 NOTICE:  Renaming the new table to alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
-ERROR:  shard name abcde_01234567890123456789012345678901234567890_f7ff6612_361345 exceeds 63 characters
+DEBUG:  the name of the shard (abcde_01234567890123456789012345678901234567890_f7ff6612_xxxxxx) for relation (abcde_012345678901234567890123456789012345678901234567890123456) is too long, switching to sequential and local execution mode to prevent self deadlocks
-CONTEXT:  while executing command on localhost:xxxxx
+CONTEXT:  SQL statement "ALTER TABLE alter_distributed_table.abcde_0123456789012345678901234567890123456_f7ff6612_4160710162 RENAME TO abcde_012345678901234567890123456789012345678901234567890123456"
-SQL statement "ALTER TABLE alter_distributed_table.abcde_0123456789012345678901234567890123456_f7ff6612_4160710162 RENAME TO abcde_012345678901234567890123456789012345678901234567890123456"
+ alter_distributed_table
+---------------------------------------------------------------------
+
+(1 row)
+
 RESET client_min_messages;
 -- test long partitioned table names
 CREATE TABLE partition_lengths
@@ -884,18 +889,33 @@ NOTICE:  creating a new table for alter_distributed_table.partition_lengths_p202
 NOTICE:  Moving the data of alter_distributed_table.partition_lengths_p2020_09_28_123456789012345678901234567890123
 NOTICE:  Dropping the old alter_distributed_table.partition_lengths_p2020_09_28_123456789012345678901234567890123
 NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths_p2020_09_28_123456789012345678901234567890123
-ERROR:  shard name partition_lengths_p2020_09_28_12345678901234567_6d0d7fee_361356 exceeds 63 characters
+NOTICE:  creating a new table for alter_distributed_table.partition_lengths
-CONTEXT:  while executing command on localhost:xxxxx
+NOTICE:  Dropping the old alter_distributed_table.partition_lengths
-SQL statement "ALTER TABLE alter_distributed_table.partition_lengths_p2020_09_28_1234567890123_6d0d7fee_1829601262 RENAME TO partition_lengths_p2020_09_28_123456789012345678901234567890123"
+NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths
+ alter_distributed_table
+---------------------------------------------------------------------
+
+(1 row)
+
 -- test long partition table names
 ALTER TABLE partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890 RENAME TO partition_lengths_p2020_09_28;
 NOTICE:  identifier "partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_28_123456789012345678901234567890123"
 ALTER TABLE partition_lengths RENAME TO partition_lengths_12345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "partition_lengths_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_123456789012345678901234567890123456789012345"
-ERROR:  shard name partition_lengths_12345678901234567890123456789_f3bd8571_361348 exceeds 63 characters
-CONTEXT:  while executing command on localhost:xxxxx
 -- verify alter_distributed_table works with long partitioned table names
 SELECT alter_distributed_table('partition_lengths_12345678901234567890123456789012345678901234567890', shard_count := 17, cascade_to_colocated := false);
-ERROR:  relation "partition_lengths_123456789012345678901234567890123456789012345" does not exist
+NOTICE:  converting the partitions of alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+NOTICE:  creating a new table for alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  Moving the data of alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  Dropping the old alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  creating a new table for alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+NOTICE:  Dropping the old alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+ alter_distributed_table
+---------------------------------------------------------------------
+
+(1 row)
+
 SET client_min_messages TO WARNING;
 DROP SCHEMA alter_distributed_table CASCADE;

src/test/regress/expected/alter_distributed_table_0.out

@@ -827,6 +827,7 @@ SELECT create_distributed_table('abcde_01234567890123456789012345678901234567890
 (1 row)
 
 SELECT alter_distributed_table('abcde_0123456789012345678901234567890123456789012345678901234567890123456789', distribution_column := 'y');
+DEBUG:  the name of the shard (abcde_01234567890123456789012345678901234567890_f7ff6612_xxxxxx) for relation (abcde_012345678901234567890123456789012345678901234567890123456) is too long, switching to sequential and local execution mode to prevent self deadlocks
 NOTICE:  creating a new table for alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
 NOTICE:  Moving the data of alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
 DEBUG:  cannot perform distributed INSERT INTO ... SELECT because the partition columns in the source table and subquery do not match
@@ -837,9 +838,13 @@ CONTEXT:  SQL statement "INSERT INTO alter_distributed_table.abcde_0123456789012
 NOTICE:  Dropping the old alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
 CONTEXT:  SQL statement "DROP TABLE alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456 CASCADE"
 NOTICE:  Renaming the new table to alter_distributed_table.abcde_012345678901234567890123456789012345678901234567890123456
-ERROR:  shard name abcde_01234567890123456789012345678901234567890_f7ff6612_361221 exceeds 63 characters
+DEBUG:  the name of the shard (abcde_01234567890123456789012345678901234567890_f7ff6612_xxxxxx) for relation (abcde_012345678901234567890123456789012345678901234567890123456) is too long, switching to sequential and local execution mode to prevent self deadlocks
-CONTEXT:  while executing command on localhost:xxxxx
+CONTEXT:  SQL statement "ALTER TABLE alter_distributed_table.abcde_0123456789012345678901234567890123456_f7ff6612_4160710162 RENAME TO abcde_012345678901234567890123456789012345678901234567890123456"
-SQL statement "ALTER TABLE alter_distributed_table.abcde_0123456789012345678901234567890123456_f7ff6612_4160710162 RENAME TO abcde_012345678901234567890123456789012345678901234567890123456"
+ alter_distributed_table
+---------------------------------------------------------------------
+
+(1 row)
+
 RESET client_min_messages;
 -- test long partitioned table names
 CREATE TABLE partition_lengths
@@ -863,18 +868,33 @@ NOTICE:  creating a new table for alter_distributed_table.partition_lengths_p202
 NOTICE:  Moving the data of alter_distributed_table.partition_lengths_p2020_09_28_123456789012345678901234567890123
 NOTICE:  Dropping the old alter_distributed_table.partition_lengths_p2020_09_28_123456789012345678901234567890123
 NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths_p2020_09_28_123456789012345678901234567890123
-ERROR:  shard name partition_lengths_p2020_09_28_12345678901234567_6d0d7fee_361233 exceeds 63 characters
+NOTICE:  creating a new table for alter_distributed_table.partition_lengths
-CONTEXT:  while executing command on localhost:xxxxx
+NOTICE:  Dropping the old alter_distributed_table.partition_lengths
-SQL statement "ALTER TABLE alter_distributed_table.partition_lengths_p2020_09_28_1234567890123_6d0d7fee_1829601262 RENAME TO partition_lengths_p2020_09_28_123456789012345678901234567890123"
+NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths
+ alter_distributed_table
+---------------------------------------------------------------------
+
+(1 row)
+
 -- test long partition table names
 ALTER TABLE partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890 RENAME TO partition_lengths_p2020_09_28;
 NOTICE:  identifier "partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_28_123456789012345678901234567890123"
 ALTER TABLE partition_lengths RENAME TO partition_lengths_12345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "partition_lengths_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_123456789012345678901234567890123456789012345"
-ERROR:  shard name partition_lengths_12345678901234567890123456789_f3bd8571_361225 exceeds 63 characters
-CONTEXT:  while executing command on localhost:xxxxx
 -- verify alter_distributed_table works with long partitioned table names
 SELECT alter_distributed_table('partition_lengths_12345678901234567890123456789012345678901234567890', shard_count := 17, cascade_to_colocated := false);
-ERROR:  relation "partition_lengths_123456789012345678901234567890123456789012345" does not exist
+NOTICE:  converting the partitions of alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+NOTICE:  creating a new table for alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  Moving the data of alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  Dropping the old alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths_p2020_09_28
+NOTICE:  creating a new table for alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+NOTICE:  Dropping the old alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+NOTICE:  Renaming the new table to alter_distributed_table.partition_lengths_123456789012345678901234567890123456789012345
+ alter_distributed_table
+---------------------------------------------------------------------
+
+(1 row)
+
 SET client_min_messages TO WARNING;
 DROP SCHEMA alter_distributed_table CASCADE;

src/test/regress/expected/alter_table_set_access_method.out

@@ -692,6 +692,7 @@ SELECT create_distributed_table('abcde_01234567890123456789012345678901234567890
 (1 row)
 
 SELECT alter_table_set_access_method('abcde_0123456789012345678901234567890123456789012345678901234567890123456789', 'columnar');
+DEBUG:  the name of the shard (abcde_01234567890123456789012345678901234567890_f7ff6612_xxxxxx) for relation (abcde_012345678901234567890123456789012345678901234567890123456) is too long, switching to sequential and local execution mode to prevent self deadlocks
 NOTICE:  creating a new table for alter_table_set_access_method.abcde_012345678901234567890123456789012345678901234567890123456
 DEBUG:  pathlist hook for columnar table am
 CONTEXT:  SQL statement "SELECT EXISTS (SELECT 1 FROM alter_table_set_access_method.abcde_0123456789012345678901234567890123456_f7ff6612_4160710162)"
@@ -699,11 +700,16 @@ NOTICE:  Moving the data of alter_table_set_access_method.abcde_0123456789012345
 NOTICE:  Dropping the old alter_table_set_access_method.abcde_012345678901234567890123456789012345678901234567890123456
 CONTEXT:  SQL statement "DROP TABLE alter_table_set_access_method.abcde_012345678901234567890123456789012345678901234567890123456 CASCADE"
 NOTICE:  Renaming the new table to alter_table_set_access_method.abcde_012345678901234567890123456789012345678901234567890123456
-ERROR:  shard name abcde_01234567890123456789012345678901234567890_f7ff6612_360901 exceeds 63 characters
+DEBUG:  the name of the shard (abcde_01234567890123456789012345678901234567890_f7ff6612_xxxxxx) for relation (abcde_012345678901234567890123456789012345678901234567890123456) is too long, switching to sequential and local execution mode to prevent self deadlocks
-CONTEXT:  while executing command on localhost:xxxxx
+CONTEXT:  SQL statement "ALTER TABLE alter_table_set_access_method.abcde_0123456789012345678901234567890123456_f7ff6612_4160710162 RENAME TO abcde_012345678901234567890123456789012345678901234567890123456"
-SQL statement "ALTER TABLE alter_table_set_access_method.abcde_0123456789012345678901234567890123456_f7ff6612_4160710162 RENAME TO abcde_012345678901234567890123456789012345678901234567890123456"
+ alter_table_set_access_method
+---------------------------------------------------------------------
+
+(1 row)
+
 SELECT * FROM abcde_0123456789012345678901234567890123456789012345678901234567890123456789;
 NOTICE:  identifier "abcde_0123456789012345678901234567890123456789012345678901234567890123456789" will be truncated to "abcde_012345678901234567890123456789012345678901234567890123456"
+DEBUG:  pathlist hook for columnar table am
  x | y
 ---------------------------------------------------------------------
 (0 rows)

src/test/regress/expected/multi_generate_ddl_commands.out

@@ -180,14 +180,10 @@ NOTICE:  foreign-data wrapper "fake_fdw" does not have an extension defined
 
 ALTER FOREIGN TABLE foreign_table rename to renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890" will be truncated to "renamed_foreign_table_with_long_name_12345678901234567890123456"
-ERROR:  shard name renamed_foreign_table_with_long_name_1234567890_6a8dd6f8_610008 exceeds 63 characters
-CONTEXT:  while executing command on localhost:xxxxx
 ALTER FOREIGN TABLE renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890 rename full_name to rename_name;
 NOTICE:  identifier "renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890" will be truncated to "renamed_foreign_table_with_long_name_12345678901234567890123456"
-ERROR:  relation "renamed_foreign_table_with_long_name_12345678901234567890123456" does not exist
 ALTER FOREIGN TABLE renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890 alter rename_name type char(8);
 NOTICE:  identifier "renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890" will be truncated to "renamed_foreign_table_with_long_name_12345678901234567890123456"
-ERROR:  relation "renamed_foreign_table_with_long_name_12345678901234567890123456" does not exist
 \c - - :public_worker_1_host :worker_1_port
 select table_name, column_name, data_type
 from information_schema.columns
@@ -195,11 +191,22 @@ where table_schema='public' and table_name like 'renamed_foreign_table_%' and co
 order by table_name;
                            table_name                            | column_name | data_type
 ---------------------------------------------------------------------
-(0 rows)
+ renamed_foreign_table_with_long_name_1234567890_6a8dd6f8_610008 | rename_name | character
+ renamed_foreign_table_with_long_name_1234567890_6a8dd6f8_610009 | rename_name | character
+ renamed_foreign_table_with_long_name_1234567890_6a8dd6f8_610010 | rename_name | character
+ renamed_foreign_table_with_long_name_1234567890_6a8dd6f8_610011 | rename_name | character
+(4 rows)
 
 \c - - :master_host :master_port
 SELECT master_get_table_ddl_events('renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890');
-ERROR:  relation "renamed_foreign_table_with_long_name_12345678901234567890123456" does not exist
+NOTICE:  foreign-data wrapper "fake_fdw" does not have an extension defined
+                                                                                                        master_get_table_ddl_events
+---------------------------------------------------------------------
+ CREATE SERVER IF NOT EXISTS fake_fdw_server FOREIGN DATA WRAPPER fake_fdw
+ CREATE FOREIGN TABLE public.renamed_foreign_table_with_long_name_12345678901234567890123456 (id bigint NOT NULL, rename_name character(8) DEFAULT ''::text NOT NULL) SERVER fake_fdw_server OPTIONS (encoding 'utf-8', compression 'true')
+ ALTER TABLE public.renamed_foreign_table_with_long_name_12345678901234567890123456 OWNER TO postgres
+(3 rows)
+
 -- propagating views is not supported
 CREATE VIEW local_view AS SELECT * FROM simple_table;
 SELECT master_get_table_ddl_events('local_view');
@@ -208,7 +215,6 @@ ERROR:  local_view is not a regular, foreign or partitioned table
 DROP VIEW IF EXISTS local_view;
 DROP FOREIGN TABLE IF EXISTS renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "renamed_foreign_table_with_long_name_12345678901234567890123456789012345678901234567890" will be truncated to "renamed_foreign_table_with_long_name_12345678901234567890123456"
-NOTICE:  foreign table "renamed_foreign_table_with_long_name_12345678901234567890123456" does not exist, skipping
 \c - - :public_worker_1_host :worker_1_port
 select table_name, column_name, data_type
 from information_schema.columns

src/test/regress/expected/multi_name_lengths.out

@@ -129,13 +129,13 @@ SELECT "Constraint", "Definition" FROM table_checks WHERE relid='public.name_len
 SET client_min_messages TO DEBUG1;
 SET citus.force_max_query_parallelization TO ON;
 ALTER TABLE name_lengths RENAME TO name_len_12345678901234567890123456789012345678901234567890;
-ERROR:  shard name name_len_12345678901234567890123456789012345678_fcd8ab6f_xxxxx exceeds 63 characters
+DEBUG:  the name of the shard (name_len_12345678901234567890123456789012345678_fcd8ab6f_xxxxx) for relation (name_len_12345678901234567890123456789012345678901234567890) is too long, switching to sequential and local execution mode to prevent self deadlocks
-CONTEXT:  while executing command on localhost:xxxxx
 SELECT * FROM name_len_12345678901234567890123456789012345678901234567890;
-DEBUG:  relation "name_len_12345678901234567890123456789012345678901234567890" does not exist
+ col1 | col2 | float_col_12345678901234567890123456789012345678901234567890 | date_col_12345678901234567890123456789012345678901234567890 | int_col_12345678901234567890123456789012345678901234567890
-ERROR:  relation "name_len_12345678901234567890123456789012345678901234567890" does not exist
+---------------------------------------------------------------------
+(0 rows)
+
 ALTER TABLE name_len_12345678901234567890123456789012345678901234567890 RENAME TO name_lengths;
-ERROR:  relation "name_len_12345678901234567890123456789012345678901234567890" does not exist
 SELECT * FROM name_lengths;
  col1 | col2 | float_col_12345678901234567890123456789012345678901234567890 | date_col_12345678901234567890123456789012345678901234567890 | int_col_12345678901234567890123456789012345678901234567890
 ---------------------------------------------------------------------
@@ -155,16 +155,15 @@ NOTICE:  identifier "append_zero_shard_table_12345678901234567890123456789012345
 BEGIN;
 ALTER TABLE name_lengths rename col1 to new_column_name;
 ALTER TABLE name_lengths RENAME TO name_len_12345678901234567890123456789012345678901234567890;
-ERROR:  shard name name_len_12345678901234567890123456789012345678_fcd8ab6f_xxxxx exceeds 63 characters
+ERROR:  Shard name (name_len_12345678901234567890123456789012345678_fcd8ab6f_xxxxx) for table (name_len_12345678901234567890123456789012345678901234567890) is too long and could lead to deadlocks when executed in a transaction block after a parallel query
-CONTEXT:  while executing command on localhost:xxxxx
+HINT:  Try re-running the transaction with "SET LOCAL citus.multi_shard_modify_mode TO 'sequential';"
 ROLLBACK;
 -- The same operation will work when sequential mode is set
 BEGIN;
 SET LOCAL citus.multi_shard_modify_mode TO 'sequential';
 ALTER TABLE name_lengths rename col1 to new_column_name;
 ALTER TABLE name_lengths RENAME TO name_len_12345678901234567890123456789012345678901234567890;
-ERROR:  shard name name_len_12345678901234567890123456789012345678_fcd8ab6f_xxxxx exceeds 63 characters
+DEBUG:  the name of the shard (name_len_12345678901234567890123456789012345678_fcd8ab6f_xxxxx) for relation (name_len_12345678901234567890123456789012345678901234567890) is too long, switching to sequential and local execution mode to prevent self deadlocks
-CONTEXT:  while executing command on localhost:xxxxx
 ROLLBACK;
 RESET client_min_messages;
 -- test long partitioned table renames
@@ -184,28 +183,23 @@ CREATE TABLE partition_lengths_p2020_09_28 PARTITION OF partition_lengths FOR VA
 -- verify that we can rename partitioned tables and partitions to too-long names
 ALTER TABLE partition_lengths RENAME TO partition_lengths_12345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "partition_lengths_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_123456789012345678901234567890123456789012345"
-ERROR:  shard name partition_lengths_12345678901234567890123456789_f3bd8571_225005 exceeds 63 characters
-CONTEXT:  while executing command on localhost:xxxxx
 -- verify that we can rename partitioned tables and partitions with too-long names
 ALTER TABLE partition_lengths_12345678901234567890123456789012345678901234567890 RENAME TO partition_lengths;
 NOTICE:  identifier "partition_lengths_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_123456789012345678901234567890123456789012345"
-ERROR:  relation "partition_lengths_123456789012345678901234567890123456789012345" does not exist
 -- Placeholders for unsupported operations
 \set VERBOSITY TERSE
 -- renaming distributed table partitions
 ALTER TABLE partition_lengths_p2020_09_28 RENAME TO partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_28_123456789012345678901234567890123"
-ERROR:  shard name partition_lengths_p2020_09_28_12345678901234567_6d0d7fee_225008 exceeds 63 characters
 -- creating or attaching new partitions with long names create deadlocks
 CREATE TABLE partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890 (LIKE partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890);
 NOTICE:  identifier "partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_29_123456789012345678901234567890123"
 NOTICE:  identifier "partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_28_123456789012345678901234567890123"
-ERROR:  relation "partition_lengths_p2020_09_28_123456789012345678901234567890123" does not exist at character 101
 ALTER TABLE partition_lengths
     ATTACH PARTITION partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890
     FOR VALUES FROM ('2020-09-29 00:00:00') TO ('2020-09-30 00:00:00');
 NOTICE:  identifier "partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_29_123456789012345678901234567890123"
-ERROR:  relation "partition_lengths_p2020_09_29_123456789012345678901234567890123" does not exist
+ERROR:  canceling the transaction since it was involved in a distributed deadlock
 CREATE TABLE partition_lengths_p2020_09_30_12345678901234567890123456789012345678901234567890
     PARTITION OF partition_lengths
     FOR VALUES FROM ('2020-09-30 00:00:00') TO ('2020-10-01 00:00:00');
@@ -213,24 +207,20 @@ NOTICE:  identifier "partition_lengths_p2020_09_30_12345678901234567890123456789
 ERROR:  canceling the transaction since it was involved in a distributed deadlock
 DROP TABLE partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_29_123456789012345678901234567890123"
-ERROR:  table "partition_lengths_p2020_09_29_123456789012345678901234567890123" does not exist
 -- creating or attaching new partitions with long names work when using sequential shard modify mode
 BEGIN;
 SET LOCAL citus.multi_shard_modify_mode = sequential;
 CREATE TABLE partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890 (LIKE partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890);
 NOTICE:  identifier "partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_29_123456789012345678901234567890123"
 NOTICE:  identifier "partition_lengths_p2020_09_28_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_28_123456789012345678901234567890123"
-ERROR:  relation "partition_lengths_p2020_09_28_123456789012345678901234567890123" does not exist at character 101
 ALTER TABLE partition_lengths
     ATTACH PARTITION partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890
     FOR VALUES FROM ('2020-09-29 00:00:00') TO ('2020-09-30 00:00:00');
 NOTICE:  identifier "partition_lengths_p2020_09_29_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_29_123456789012345678901234567890123"
-ERROR:  current transaction is aborted, commands ignored until end of transaction block
 CREATE TABLE partition_lengths_p2020_09_30_12345678901234567890123456789012345678901234567890
     PARTITION OF partition_lengths
     FOR VALUES FROM ('2020-09-30 00:00:00') TO ('2020-10-01 00:00:00');
 NOTICE:  identifier "partition_lengths_p2020_09_30_12345678901234567890123456789012345678901234567890" will be truncated to "partition_lengths_p2020_09_30_123456789012345678901234567890123"
-ERROR:  current transaction is aborted, commands ignored until end of transaction block
 ROLLBACK;
 -- renaming distributed table constraints are not supported
 ALTER TABLE name_lengths RENAME CONSTRAINT unique_12345678901234567890123456789012345678901234567890 TO unique2_12345678901234567890123456789012345678901234567890;
@@ -261,17 +251,15 @@ NOTICE:  identifier "tmp_idx_123456789012345678901234567890123456789012345678901
 ALTER INDEX tmp_idx_123456789012345678901234567890123456789012345678901234567890 RENAME TO tmp_idx_newname_123456789012345678901234567890123456789012345678901234567890;
 NOTICE:  identifier "tmp_idx_123456789012345678901234567890123456789012345678901234567890" will be truncated to "tmp_idx_1234567890123456789012345678901234567890123456789012345"
 NOTICE:  identifier "tmp_idx_newname_123456789012345678901234567890123456789012345678901234567890" will be truncated to "tmp_idx_newname_12345678901234567890123456789012345678901234567"
-ERROR:  shard name tmp_idx_newname_1234567890123456789012345678901_c54e849b_225002 exceeds 63 characters
-CONTEXT:  while executing command on localhost:xxxxx
 \c - - :public_worker_1_host :worker_1_port
 SELECT "relname", "Column", "Type", "Definition" FROM index_attrs WHERE
     relname LIKE 'tmp_idx_%' ORDER BY 1 DESC, 2 DESC, 3 DESC, 4 DESC;
                              relname                             | Column |  Type   | Definition
 ---------------------------------------------------------------------
+ tmp_idx_newname_1234567890123456789012345678901_c54e849b_225003 | col2   | integer | col2
+ tmp_idx_newname_1234567890123456789012345678901_c54e849b_225002 | col2   | integer | col2
  tmp_idx_123456789012345678901234567890123456789_5e470afa_225003 | col2   | integer | col2
  tmp_idx_123456789012345678901234567890123456789_5e470afa_225002 | col2   | integer | col2
- tmp_idx_123456789012345678901234567890123456789_599636aa_225003 | col2   | integer | col2
- tmp_idx_123456789012345678901234567890123456789_599636aa_225002 | col2   | integer | col2
 (4 rows)
 
 \c - - :master_host :master_port
@@ -327,10 +315,15 @@ SELECT master_create_worker_shards('sneaky_name_lengths', '2', '2');
                                                     List of relations
  Schema |                              Name                               | Type  |  Owner   |           Table
 ---------------------------------------------------------------------
-(0 rows)
+ public | sneaky_name_lengths_int_col_1234567890123456789_6402d2cd_225030 | index | postgres | sneaky_name_lengths_225030
+(1 row)
 
 SELECT "Constraint", "Definition" FROM table_checks WHERE relid='public.sneaky_name_lengths_225030'::regclass ORDER BY 1 DESC, 2 DESC;
-ERROR:  relation "public.sneaky_name_lengths_225030" does not exist
+                        Constraint                         |                                  Definition
+---------------------------------------------------------------------
+ checky_12345678901234567890123456789012345678901234567890 | CHECK (int_col_123456789012345678901234567890123456789012345678901234 > 100)
+(1 row)
+
 \c - - :master_host :master_port
 SET citus.shard_count TO 2;
 SET citus.shard_replication_factor TO 2;
@@ -353,7 +346,8 @@ SELECT create_distributed_table('sneaky_name_lengths', 'col1', 'hash');
                                                     List of relations
  Schema |                              Name                               | Type  |  Owner   |           Table
 ---------------------------------------------------------------------
-(0 rows)
+ public | unique_1234567890123456789012345678901234567890_a5986f27_225032 | index | postgres | sneaky_name_lengths_225032
+(1 row)
 
 \c - - :master_host :master_port
 SET citus.shard_count TO 2;