Subject: Re: Add SPLIT PARTITION/MERGE PARTITIONS commands

From: stephane tachoires <[email-masked]>
Date: Wed, 29 Mar 2023 10:13:37 +0000

The following review has been posted through the commitfest application:
make installcheck-world:  tested, passed
Implements feature:       tested, passed
Spec compliant:           tested, passed
Documentation:            tested, failed

Hi,
Just a minor warning with documentation patch 
git apply ../v16-0003-Documentation-for-ALTER-TABLE-SPLIT-PARTITION-ME.patch
../v16-0003-Documentation-for-ALTER-TABLE-SPLIT-PARTITION-ME.patch:54: trailing whitespace.
      One of the new partitions <replaceable class="parameter">partition_name1</replaceable>, 
warning: 1 ligne a ajouté des erreurs d'espace.
(perhaps due to my Ubuntu 22.04.2 french install)
Everything else is ok.

Thanks a lot for your work
Stéphane

---

From: Dmitry Koval <[email-masked]>
Date: Wed, 29 Mar 2023 16:32:36 +0300

Thanks!

I missed the trailing whitespace.
Corrected.

-- 
With best regards,
Dmitry Koval

Postgres Professional: http://postgrespro.com

From fa3a3cde9035092ad2812b7353cfbec9cbc29d2c Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 16:06:03 +0300
Subject: [PATCH v17 1/3] ALTER TABLE MERGE PARTITIONS command

---
 src/backend/commands/tablecmds.c              | 351 ++++++++-
 src/backend/parser/gram.y                     |  22 +-
 src/backend/parser/parse_utilcmd.c            |  89 +++
 src/backend/partitioning/partbounds.c         | 207 +++++
 src/include/nodes/parsenodes.h                |  13 +
 src/include/parser/kwlist.h                   |   1 +
 src/include/partitioning/partbounds.h         |   6 +
 .../isolation/expected/partition-merge.out    | 199 +++++
 src/test/isolation/isolation_schedule         |   1 +
 src/test/isolation/specs/partition-merge.spec |  54 ++
 .../test_ddl_deparse/test_ddl_deparse.c       |   3 +
 src/test/regress/expected/partition_merge.out | 736 ++++++++++++++++++
 src/test/regress/parallel_schedule            |   2 +-
 src/test/regress/sql/partition_merge.sql      | 434 +++++++++++
 src/tools/pgindent/typedefs.list              |   1 +
 15 files changed, 2100 insertions(+), 19 deletions(-)
 create mode 100644 src/test/isolation/expected/partition-merge.out
 create mode 100644 src/test/isolation/specs/partition-merge.spec
 create mode 100644 src/test/regress/expected/partition_merge.out
 create mode 100644 src/test/regress/sql/partition_merge.sql

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 3147dddf28..49e9340d5c 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -638,6 +638,8 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);
 
+static void ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel,
+								  PartitionCmd *cmd, AlterTableUtilityContext *context);
 
 /* ----------------------------------------------------------------
  *		DefineRelation
@@ -4476,6 +4478,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
+			case AT_MergePartitions:
+				cmd_lockmode = AccessExclusiveLock;
+				break;
+
 			case AT_CheckNotNull:
 
 				/*
@@ -4897,6 +4903,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			/* No command-specific prep needed */
 			pass = AT_PASS_MISC;
 			break;
+		case AT_MergePartitions:
+			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
+			/* No command-specific prep needed */
+			pass = AT_PASS_MISC;
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -5284,6 +5295,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
 		case AT_DetachPartitionFinalize:
 			address = ATExecDetachPartitionFinalize(rel, ((PartitionCmd *) cmd->def)->name);
 			break;
+		case AT_MergePartitions:
+			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
+									  cur_pass, context);
+			Assert(cmd != NULL);
+			Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
+			ATExecMergePartitions(wqueue, tab, rel, (PartitionCmd *) cmd->def,
+								  context);
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -6267,6 +6286,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
 			return "DETACH PARTITION";
 		case AT_DetachPartitionFinalize:
 			return "DETACH PARTITION ... FINALIZE";
+		case AT_MergePartitions:
+			return "MERGE PARTITIONS";
 		case AT_AddIdentity:
 			return "ALTER COLUMN ... ADD IDENTITY";
 		case AT_SetIdentity:
@@ -17699,6 +17720,37 @@ QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
 	}
 }
 
+/*
+ * attachPartitionTable: attach new partition to partitioned table
+ *
+ * wqueue: the ALTER TABLE work queue; can be NULL when not running as part
+ *   of an ALTER TABLE sequence.
+ * rel: partitioned relation;
+ * partition: relation of attached partition;
+ * bound: bounds of attached relation.
+ */
+static void
+attachPartitionTable(List **wqueue, Relation rel, Relation partition, PartitionBoundSpec *bound)
+{
+	/* OK to create inheritance.  Rest of the checks performed there */
+	CreateInheritance(partition, rel);
+
+	/* Update the pg_class entry. */
+	StorePartitionBound(partition, rel, bound);
+
+	/* Ensure there exists a correct set of indexes in the partition. */
+	AttachPartitionEnsureIndexes(rel, partition);
+
+	/* and triggers */
+	CloneRowTriggersToPartition(rel, partition);
+
+	/*
+	 * Clone foreign key constraints.  Callee is responsible for setting up
+	 * for phase 3 constraint verification.
+	 */
+	CloneForeignKeyConstraints(wqueue, rel, partition);
+}
+
 /*
  * ALTER TABLE <name> ATTACH PARTITION <partition-name> FOR VALUES
  *
@@ -17891,23 +17943,8 @@ ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd,
 	check_new_partition_bound(RelationGetRelationName(attachrel), rel,
 							  cmd->bound, pstate);
 
-	/* OK to create inheritance.  Rest of the checks performed there */
-	CreateInheritance(attachrel, rel);
-
-	/* Update the pg_class entry. */
-	StorePartitionBound(attachrel, rel, cmd->bound);
-
-	/* Ensure there exists a correct set of indexes in the partition. */
-	AttachPartitionEnsureIndexes(rel, attachrel);
-
-	/* and triggers */
-	CloneRowTriggersToPartition(rel, attachrel);
-
-	/*
-	 * Clone foreign key constraints.  Callee is responsible for setting up
-	 * for phase 3 constraint verification.
-	 */
-	CloneForeignKeyConstraints(wqueue, rel, attachrel);
+	/* Attach partition to partitioned table. */
+	attachPartitionTable(wqueue, rel, attachrel, cmd->bound);
 
 	/*
 	 * Generate partition constraint from the partition bound specification.
@@ -19388,3 +19425,283 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 
 	return cstorage;
 }
+
+/*
+ * createPartitionTable: create table for new partition with given name
+ * (newPartName) like table (modelRelName)
+ *
+ * Emulates command: CREATE TABLE <newPartName> (LIKE <modelRelName>
+ * INCLUDING ALL EXCLUDING INDEXES)
+ */
+static void
+createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
+					 AlterTableUtilityContext *context)
+{
+	CreateStmt *createStmt;
+	TableLikeClause *tlc;
+	PlannedStmt *wrapper;
+
+	createStmt = makeNode(CreateStmt);
+	createStmt->relation = newPartName;
+	createStmt->tableElts = NIL;
+	createStmt->inhRelations = NIL;
+	createStmt->constraints = NIL;
+	createStmt->options = NIL;
+	createStmt->oncommit = ONCOMMIT_NOOP;
+	createStmt->tablespacename = NULL;
+	createStmt->if_not_exists = false;
+
+	tlc = makeNode(TableLikeClause);
+	tlc->relation = modelRelName;
+
+	/*
+	 * Indexes will be inherited on "attach new partitions" stage, after data
+	 * moving.
+	 */
+	tlc->options = CREATE_TABLE_LIKE_ALL & ~CREATE_TABLE_LIKE_INDEXES;
+	tlc->relationOid = InvalidOid;
+	createStmt->tableElts = lappend(createStmt->tableElts, tlc);
+
+	/* Need to make a wrapper PlannedStmt. */
+	wrapper = makeNode(PlannedStmt);
+	wrapper->commandType = CMD_UTILITY;
+	wrapper->canSetTag = false;
+	wrapper->utilityStmt = (Node *) createStmt;
+	wrapper->stmt_location = context->pstmt->stmt_location;
+	wrapper->stmt_len = context->pstmt->stmt_len;
+
+	ProcessUtility(wrapper,
+				   context->queryString,
+				   false,
+				   PROCESS_UTILITY_SUBCOMMAND,
+				   NULL,
+				   NULL,
+				   None_Receiver,
+				   NULL);
+}
+
+/*
+ * Struct with context of merged partition
+ */
+typedef struct MergedPartContext
+{
+	Relation	partRel;		/* relation for partition */
+}			MergedPartContext;
+
+/*
+ * moveMergedTablesRows: scan merged partitions (partContext) of partitioned
+ * table (rel) and move rows into new partition (newPartRel).
+ */
+static void
+moveMergedTablesRows(Relation rel, List *partContext, Relation newPartRel)
+{
+	CommandId	mycid;
+
+	/* The FSM is empty, so don't bother using it. */
+	int			ti_options = TABLE_INSERT_SKIP_FSM;
+	ListCell   *listptr;
+	BulkInsertState bistate;	/* state of bulk inserts for partition */
+	TupleTableSlot *dstslot;
+
+	mycid = GetCurrentCommandId(true);
+
+	/* Prepare a BulkInsertState for table_tuple_insert. */
+	bistate = GetBulkInsertState();
+
+	/* Create necessary tuple slot. */
+	dstslot = MakeSingleTupleTableSlot(RelationGetDescr(newPartRel),
+									   table_slot_callbacks(newPartRel));
+	ExecStoreAllNullTuple(dstslot);
+
+	foreach(listptr, partContext)
+	{
+		MergedPartContext *pc = (MergedPartContext *) lfirst(listptr);
+		TupleTableSlot *srcslot;
+		TupleConversionMap *tuple_map;
+		TableScanDesc scan;
+		Snapshot	snapshot;
+
+		/* Create tuple slot for new partition. */
+		srcslot = MakeSingleTupleTableSlot(RelationGetDescr(pc->partRel),
+										   table_slot_callbacks(pc->partRel));
+
+		/*
+		 * Map computing for moving attributes of merged partition to new
+		 * partition.
+		 */
+		tuple_map = convert_tuples_by_name(RelationGetDescr(pc->partRel),
+										   RelationGetDescr(newPartRel));
+
+		/* Scan through the rows. */
+		snapshot = RegisterSnapshot(GetLatestSnapshot());
+		scan = table_beginscan(pc->partRel, snapshot, 0, NULL);
+
+		while (table_scan_getnextslot(scan, ForwardScanDirection, srcslot))
+		{
+			TupleTableSlot *insertslot;
+
+			/* Extract data from old tuple. */
+			slot_getallattrs(srcslot);
+
+			if (tuple_map)
+			{
+				/* Need to use map for copy attributes. */
+				insertslot = execute_attr_map_slot(tuple_map->attrMap, srcslot, dstslot);
+			}
+			else
+			{
+				/* Copy attributes directly. */
+				insertslot = dstslot;
+
+				ExecClearTuple(insertslot);
+
+				memcpy(insertslot->tts_values, srcslot->tts_values,
+					   sizeof(Datum) * srcslot->tts_nvalid);
+				memcpy(insertslot->tts_isnull, srcslot->tts_isnull,
+					   sizeof(bool) * srcslot->tts_nvalid);
+
+				ExecStoreVirtualTuple(insertslot);
+			}
+
+			/* Write the tuple out to the new relation. */
+			table_tuple_insert(newPartRel, insertslot, mycid, ti_options, bistate);
+
+			CHECK_FOR_INTERRUPTS();
+		}
+
+		table_endscan(scan);
+		UnregisterSnapshot(snapshot);
+
+		if (tuple_map)
+			free_conversion_map(tuple_map);
+
+		ExecDropSingleTupleTableSlot(srcslot);
+	}
+
+	ExecDropSingleTupleTableSlot(dstslot);
+	FreeBulkInsertState(bistate);
+
+	table_finish_bulk_insert(newPartRel, ti_options);
+}
+
+/*
+ * ALTER TABLE <name> MERGE PARTITIONS <partition-list> INTO <partition-name>
+ */
+static void
+ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel,
+					  PartitionCmd *cmd, AlterTableUtilityContext *context)
+{
+	Relation	newPartRel;
+	ListCell   *listptr;
+	List	   *partContexts = NIL;
+	Oid			defaultPartOid;
+	char		tmpRelName[NAMEDATALEN];
+	RangeVar   *mergePartName = cmd->name;
+	bool		isSameName = false;
+
+	/*
+	 * Lock all merged partitions, check them and create list with partitions
+	 * contexts.
+	 */
+	foreach(listptr, cmd->partlist)
+	{
+		RangeVar   *name = (RangeVar *) lfirst(listptr);
+		MergedPartContext *pc;
+
+		pc = (MergedPartContext *) palloc0(sizeof(MergedPartContext));
+
+		/*
+		 * We are going to detach and remove this partition: need to use
+		 * exclusive lock for prevent DML-queries to the partition.
+		 */
+		pc->partRel = table_openrv(name, AccessExclusiveLock);
+
+		if (pc->partRel->rd_rel->relkind != RELKIND_RELATION)
+			ereport(ERROR,
+					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					 errmsg("cannot merge non-table partition \"%s\"",
+							RelationGetRelationName(pc->partRel))));
+
+		/*
+		 * Checking that two partitions have the same name was before,
+		 * in function transformPartitionCmdForMerge().
+		 */
+		if (equal(name, cmd->name))
+			/* One new partition can have the same name as merged partition. */
+			isSameName = true;
+
+		/* Store partition context into partitions list. */
+		partContexts = lappend(partContexts, pc);
+	}
+
+	/* Detach all merged partitions. */
+	defaultPartOid =
+		get_default_oid_from_partdesc(RelationGetPartitionDesc(rel, true));
+	foreach(listptr, partContexts)
+	{
+		MergedPartContext *pc = (MergedPartContext *) lfirst(listptr);
+
+		RemoveInheritance(pc->partRel, rel, false);
+		/* Do the final part of detaching. */
+		DetachPartitionFinalize(rel, pc->partRel, false, defaultPartOid);
+	}
+
+	/* Create table for new partition, use partitioned table as model. */
+	if (isSameName)
+	{
+		/* Create partition table with generated temparary name. */
+		sprintf(tmpRelName, "merge-%u-%X-tmp", RelationGetRelid(rel), MyProcPid);
+		mergePartName = makeRangeVar(get_namespace_name(RelationGetNamespace(rel)),
+									 tmpRelName, -1);
+	}
+	createPartitionTable(mergePartName,
+						 makeRangeVar(get_namespace_name(RelationGetNamespace(rel)),
+									  RelationGetRelationName(rel), -1),
+						 context);
+
+	/* Open the new partition and acquire exclusive lock on it. */
+	newPartRel = table_openrv(mergePartName, AccessExclusiveLock);
+
+	/* Copy data from merged partitions to new partition. */
+	moveMergedTablesRows(rel, partContexts, newPartRel);
+
+	/*
+	 * Attach new partition to partitioned table. wqueue = NULL: verification
+	 * for each cloned constraint is not need.
+	 */
+	attachPartitionTable(NULL, rel, newPartRel, cmd->bound);
+
+	/* Unlock and drop merged partitions. */
+	foreach(listptr, partContexts)
+	{
+		ObjectAddress object;
+		MergedPartContext *pc = (MergedPartContext *) lfirst(listptr);
+
+		/* Get relation id before table_close() call. */
+		object.objectId = RelationGetRelid(pc->partRel);
+		object.classId = RelationRelationId;
+		object.objectSubId = 0;
+
+		/* Keep the lock until commit. */
+		table_close(pc->partRel, NoLock);
+
+		performDeletion(&object, DROP_RESTRICT, 0);
+
+		pfree(pc);
+	}
+
+	/* Rename new partition if it is needed. */
+	if (isSameName)
+	{
+		/*
+		 * We must bump the command counter to make the new partition tuple
+		 * visible for rename.
+		 */
+		CommandCounterIncrement();
+		/* Rename partition. */
+		RenameRelationInternal(RelationGetRelid(newPartRel),
+							   cmd->name->relname, false, false);
+	}
+	/* Keep the lock until commit. */
+	table_close(newPartRel, NoLock);
+}
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index efe88ccf9d..ad8f68b99d 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -726,7 +726,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	ORDER ORDINALITY OTHERS OUT_P OUTER_P
 	OVER OVERLAPS OVERLAY OVERRIDING OWNED OWNER
 
-	PARALLEL PARAMETER PARSER PARTIAL PARTITION PASSING PASSWORD
+	PARALLEL PARAMETER PARSER PARTIAL PARTITION PARTITIONS PASSING PASSWORD
 	PLACING PLANS POLICY
 	POSITION PRECEDING PRECISION PRESERVE PREPARE PREPARED PRIMARY
 	PRIOR PRIVILEGES PROCEDURAL PROCEDURE PROCEDURES PROGRAM PUBLICATION
@@ -2280,6 +2280,7 @@ partition_cmd:
 					n->subtype = AT_AttachPartition;
 					cmd->name = $3;
 					cmd->bound = $4;
+					cmd->partlist = NULL;
 					cmd->concurrent = false;
 					n->def = (Node *) cmd;
 
@@ -2294,6 +2295,7 @@ partition_cmd:
 					n->subtype = AT_DetachPartition;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
 					cmd->concurrent = $4;
 					n->def = (Node *) cmd;
 
@@ -2307,6 +2309,21 @@ partition_cmd:
 					n->subtype = AT_DetachPartitionFinalize;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
+					cmd->concurrent = false;
+					n->def = (Node *) cmd;
+					$$ = (Node *) n;
+				}
+			/* ALTER TABLE <name> MERGE PARTITIONS () INTO <partition_name> */
+			| MERGE PARTITIONS '(' qualified_name_list ')' INTO qualified_name
+				{
+					AlterTableCmd *n = makeNode(AlterTableCmd);
+					PartitionCmd *cmd = makeNode(PartitionCmd);
+
+					n->subtype = AT_MergePartitions;
+					cmd->name = $7;
+					cmd->bound = NULL;
+					cmd->partlist = $4;
 					cmd->concurrent = false;
 					n->def = (Node *) cmd;
 					$$ = (Node *) n;
@@ -2323,6 +2340,7 @@ index_partition_cmd:
 					n->subtype = AT_AttachPartition;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
 					cmd->concurrent = false;
 					n->def = (Node *) cmd;
 
@@ -16905,6 +16923,7 @@ unreserved_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLANS
@@ -17488,6 +17507,7 @@ bare_label_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLACING
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 15a1dab8c5..e9fbfc0605 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -58,6 +58,8 @@
 #include "parser/parse_type.h"
 #include "parser/parse_utilcmd.h"
 #include "parser/parser.h"
+#include "partitioning/partdesc.h"
+#include "partitioning/partbounds.h"
 #include "rewrite/rewriteManip.h"
 #include "utils/acl.h"
 #include "utils/builtins.h"
@@ -3263,6 +3265,80 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
+ * transformPartitionCmdForMerge
+ *		Analyze the ALTER TABLLE ... MERGE PARTITIONS command
+ *
+ * Does simple checks for merged partitions. Calculates bound of result
+ * partition.
+ */
+static void
+transformPartitionCmdForMerge(CreateStmtContext *cxt, PartitionCmd *partcmd)
+{
+	Oid			defaultPartOid;
+	Oid			partOid;
+	Relation	parent = cxt->rel;
+	PartitionKey key;
+	char		strategy;
+	ListCell   *listptr,
+			   *listptr2;
+	bool		isDefaultPart = false;
+	List	   *partOids = NIL;
+
+	if (parent->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("\"%s\" is not a partitioned table", RelationGetRelationName(parent))));
+
+	key = RelationGetPartitionKey(parent);
+	strategy = get_partition_strategy(key);
+
+	if (strategy == PARTITION_STRATEGY_HASH)
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("partition of hash-partitioned table cannot be merged")));
+
+	/* Is current partition a DEFAULT partition? */
+	defaultPartOid = get_default_oid_from_partdesc(
+												   RelationGetPartitionDesc(parent, true));
+
+	foreach(listptr, partcmd->partlist)
+	{
+		RangeVar   *name = (RangeVar *) lfirst(listptr);
+
+		/* Partitions in the list should have different names. */
+		for_each_cell(listptr2, partcmd->partlist, lnext(partcmd->partlist, listptr))
+		{
+			RangeVar   *name2 = (RangeVar *) lfirst(listptr2);
+
+			if (equal(name, name2))
+				ereport(ERROR,
+						(errcode(ERRCODE_DUPLICATE_TABLE),
+						 errmsg("partition with name \"%s\" already used", name->relname)),
+						parser_errposition(cxt->pstate, name2->location));
+		}
+
+		/* Search DEFAULT partition in the list. */
+		partOid = RangeVarGetRelid(name, NoLock, false);
+		if (partOid == defaultPartOid)
+			isDefaultPart = true;
+		partOids = lappend_oid(partOids, partOid);
+	}
+
+	/* Allocate bound of result partition. */
+	Assert(partcmd->bound == NULL);
+	partcmd->bound = makeNode(PartitionBoundSpec);
+
+	/* Fill partition bound. */
+	partcmd->bound->strategy = strategy;
+	partcmd->bound->location = -1;
+	partcmd->bound->is_default = isDefaultPart;
+	if (!isDefaultPart)
+		calculate_partition_bound_for_merge(parent, partcmd->partlist,
+											partOids, partcmd->bound,
+											cxt->pstate);
+}
+
 /*
  * transformAlterTableStmt -
  *		parse analysis for ALTER TABLE
@@ -3532,6 +3608,19 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 				newcmds = lappend(newcmds, cmd);
 				break;
 
+			case AT_MergePartitions:
+				{
+					PartitionCmd *partcmd = (PartitionCmd *) cmd->def;
+
+					if (list_length(partcmd->partlist) < 2)
+						ereport(ERROR,
+								(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+								 errmsg("list of new partitions should contains at least two items")));
+					transformPartitionCmdForMerge(&cxt, partcmd);
+					newcmds = lappend(newcmds, cmd);
+					break;
+				}
+
 			default:
 
 				/*
diff --git a/src/backend/partitioning/partbounds.c b/src/backend/partitioning/partbounds.c
index cf1156b842..032ebae595 100644
--- a/src/backend/partitioning/partbounds.c
+++ b/src/backend/partitioning/partbounds.c
@@ -4978,3 +4978,210 @@ satisfies_hash_partition(PG_FUNCTION_ARGS)
 
 	PG_RETURN_BOOL(rowHash % modulus == remainder);
 }
+
+/*
+ * check_two_partitions_bounds_range
+ *
+ * (function for BY RANGE partitioning)
+ *
+ * This is a helper function for check_partitions_for_split() and
+ * calculate_partition_bound_for_merge().
+ * This function compares upper bound of first_bound and lower bound of
+ * second_bound. These bounds should be equals except case
+ * "defaultPart == true" (this means that one of split partitions is DEFAULT).
+ * In this case upper bound of first_bound can be less than lower bound of
+ * second_bound because space between of these bounds will be included in
+ * DEFAULT partition.
+ *
+ * parent:			partitioned table
+ * first_name:		name of first partition
+ * first_bound:		bound of first partition
+ * second_name:		name of second partition
+ * second_bound:	bound of second partition
+ * defaultPart:		true if one of split partitions is DEFAULT
+ * pstate:			pointer to ParseState struct for determine error position
+ */
+static void
+check_two_partitions_bounds_range(Relation parent,
+								  RangeVar *first_name,
+								  PartitionBoundSpec *first_bound,
+								  RangeVar *second_name,
+								  PartitionBoundSpec *second_bound,
+								  bool defaultPart,
+								  ParseState *pstate)
+{
+	PartitionKey key = RelationGetPartitionKey(parent);
+	PartitionRangeBound *first_upper;
+	PartitionRangeBound *second_lower;
+	int			cmpval;
+
+	Assert(key->strategy == PARTITION_STRATEGY_RANGE);
+
+	first_upper = make_one_partition_rbound(key, -1, first_bound->upperdatums, false);
+	second_lower = make_one_partition_rbound(key, -1, second_bound->lowerdatums, true);
+
+	/*
+	 * lower1=false (the second to last argument) for correct comparison lower
+	 * and upper bounds.
+	 */
+	cmpval = partition_rbound_cmp(key->partnatts,
+								  key->partsupfunc,
+								  key->partcollation,
+								  second_lower->datums, second_lower->kind,
+								  false, first_upper);
+	if ((!defaultPart && cmpval) || (defaultPart && cmpval < 0))
+	{
+		PartitionRangeDatum *datum = linitial(second_bound->lowerdatums);
+
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("lower bound of partition \"%s\" conflicts with upper bound of previous partition \"%s\"",
+						second_name->relname, first_name->relname),
+				 parser_errposition(pstate, datum->location)));
+	}
+}
+
+/*
+ * get_partition_bound_spec
+ *
+ * Returns description of partition with Oid "partOid" and name "name".
+ */
+static PartitionBoundSpec *
+get_partition_bound_spec(Oid partOid, RangeVar *name)
+{
+	HeapTuple	tuple;
+	Datum		datum;
+	bool		isnull;
+	PartitionBoundSpec *boundspec = NULL;
+
+	/* Try fetching the tuple from the catcache, for speed. */
+	tuple = SearchSysCache1(RELOID, partOid);
+	if (!HeapTupleIsValid(tuple))
+		elog(ERROR, "cache lookup failed for relation \"%s\"",
+			 name->relname);
+
+	datum = SysCacheGetAttr(RELOID, tuple,
+							Anum_pg_class_relpartbound,
+							&isnull);
+	if (isnull)
+		elog(ERROR, "partition bound for relation \"%s\" is null",
+			 name->relname);
+
+	boundspec = stringToNode(TextDatumGetCString(datum));
+
+	if (!IsA(boundspec, PartitionBoundSpec))
+		elog(ERROR, "expected PartitionBoundSpec for relation \"%s\"",
+			 name->relname);
+
+	ReleaseSysCache(tuple);
+	return boundspec;
+}
+
+/*
+ * calculate_partition_bound_for_merge
+ *
+ * Calculates the bound of merged partition "spec" by using the bounds of
+ * partitions to be merged.
+ *
+ * parent:			partitioned table
+ * partNames:		names of partitions to be merged
+ * partOids:		Oids of partitions to be merged
+ * spec (out):		bounds specification of the merged partition
+ * pstate:			pointer to ParseState struct for determine error position
+ */
+void
+calculate_partition_bound_for_merge(Relation parent,
+									List *partNames,
+									List *partOids,
+									PartitionBoundSpec *spec,
+									ParseState *pstate)
+{
+	PartitionKey key = RelationGetPartitionKey(parent);
+	PartitionBoundSpec *bound;
+
+	Assert(!spec->is_default);
+
+	switch (key->strategy)
+	{
+		case PARTITION_STRATEGY_RANGE:
+			{
+				int			i;
+				PartitionRangeBound **lower_bounds;
+				int			nparts = list_length(partOids);
+				List	   *bounds = NIL;
+
+				lower_bounds = (PartitionRangeBound **)
+					palloc0(nparts * sizeof(PartitionRangeBound *));
+
+				/*
+				 * Create array of lower bounds and list of
+				 * PartitionBoundSpec.
+				 */
+				for (i = 0; i < nparts; i++)
+				{
+					bound = get_partition_bound_spec(list_nth_oid(partOids, i),
+													 (RangeVar *) list_nth(partNames, i));
+
+					lower_bounds[i] = make_one_partition_rbound(key, i, bound->lowerdatums, true);
+					bounds = lappend(bounds, bound);
+				}
+
+				/* Sort array of lower bounds. */
+				qsort_arg(lower_bounds, nparts, sizeof(PartitionRangeBound *),
+						  qsort_partition_rbound_cmp, (void *) key);
+
+				/* Ranges of partitions should not overlap. */
+				for (i = 1; i < nparts; i++)
+				{
+					int			index = lower_bounds[i]->index;
+					int			prev_index = lower_bounds[i - 1]->index;
+
+					check_two_partitions_bounds_range(parent,
+													  (RangeVar *) list_nth(partNames, prev_index),
+													  (PartitionBoundSpec *) list_nth(bounds, prev_index),
+													  (RangeVar *) list_nth(partNames, index),
+													  (PartitionBoundSpec *) list_nth(bounds, index),
+													  false, pstate);
+				}
+
+				/*
+				 * Lower bound of first partition is a lower bound of merged
+				 * partition.
+				 */
+				spec->lowerdatums =
+					((PartitionBoundSpec *) list_nth(bounds, lower_bounds[0]->index))->lowerdatums;
+
+				/*
+				 * Upper bound of last partition is a upper bound of merged
+				 * partition.
+				 */
+				spec->upperdatums =
+					((PartitionBoundSpec *) list_nth(bounds, lower_bounds[nparts - 1]->index))->upperdatums;
+
+				pfree(lower_bounds);
+				list_free(bounds);
+				break;
+			}
+
+		case PARTITION_STRATEGY_LIST:
+			{
+				ListCell   *listptr,
+						   *listptr2;
+
+				/* Consolidate bounds for all partitions in the list. */
+				forboth(listptr, partOids, listptr2, partNames)
+				{
+					RangeVar   *name = (RangeVar *) lfirst(listptr2);
+					Oid			curOid = lfirst_oid(listptr);
+
+					bound = get_partition_bound_spec(curOid, name);
+					spec->listdatums = list_concat(spec->listdatums, bound->listdatums);
+				}
+				break;
+			}
+
+		default:
+			elog(ERROR, "unexpected partition strategy: %d",
+				 (int) key->strategy);
+	}
+}
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 028588fb33..f5c0625bbf 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -932,6 +932,17 @@ typedef struct PartitionRangeDatum
 	int			location;		/* token location, or -1 if unknown */
 } PartitionRangeDatum;
 
+/*
+ * PartitionDesc - info about single partition for ALTER TABLE SPLIT PARTITION command
+ */
+typedef struct SinglePartitionSpec
+{
+	NodeTag		type;
+
+	RangeVar   *name;			/* name of partition */
+	PartitionBoundSpec *bound;	/* FOR VALUES, if attaching */
+} SinglePartitionSpec;
+
 /*
  * PartitionCmd - info for ALTER TABLE/INDEX ATTACH/DETACH PARTITION commands
  */
@@ -940,6 +951,7 @@ typedef struct PartitionCmd
 	NodeTag		type;
 	RangeVar   *name;			/* name of partition to attach/detach */
 	PartitionBoundSpec *bound;	/* FOR VALUES, if attaching */
+	List	   *partlist;		/* list of partitions, for SPLIT PARTITION command */
 	bool		concurrent;
 } PartitionCmd;
 
@@ -2126,6 +2138,7 @@ typedef enum AlterTableType
 	AT_AttachPartition,			/* ATTACH PARTITION */
 	AT_DetachPartition,			/* DETACH PARTITION */
 	AT_DetachPartitionFinalize, /* DETACH PARTITION FINALIZE */
+	AT_MergePartitions,			/* MERGE PARTITIONS */
 	AT_AddIdentity,				/* ADD IDENTITY */
 	AT_SetIdentity,				/* SET identity column options */
 	AT_DropIdentity,			/* DROP IDENTITY */
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h
index 753e9ee174..2abe9d7d7d 100644
--- a/src/include/parser/kwlist.h
+++ b/src/include/parser/kwlist.h
@@ -314,6 +314,7 @@ PG_KEYWORD("parameter", PARAMETER, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("parser", PARSER, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("partial", PARTIAL, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("partition", PARTITION, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("partitions", PARTITIONS, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("passing", PASSING, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("password", PASSWORD, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("placing", PLACING, RESERVED_KEYWORD, BARE_LABEL)
diff --git a/src/include/partitioning/partbounds.h b/src/include/partitioning/partbounds.h
index d2e01f92df..2fe80fb4fc 100644
--- a/src/include/partitioning/partbounds.h
+++ b/src/include/partitioning/partbounds.h
@@ -143,4 +143,10 @@ extern int	partition_range_datum_bsearch(FmgrInfo *partsupfunc,
 extern int	partition_hash_bsearch(PartitionBoundInfo boundinfo,
 								   int modulus, int remainder);
 
+extern void calculate_partition_bound_for_merge(Relation parent,
+												List *partNames,
+												List *partOids,
+												PartitionBoundSpec *spec,
+												ParseState *pstate);
+
 #endif							/* PARTBOUNDS_H */
diff --git a/src/test/isolation/expected/partition-merge.out b/src/test/isolation/expected/partition-merge.out
new file mode 100644
index 0000000000..98446aaab5
--- /dev/null
+++ b/src/test/isolation/expected/partition-merge.out
@@ -0,0 +1,199 @@
+Parsed test spec with 2 sessions
+
+starting permutation: s2b s2i s2c s1b s1merg s2b s2u s1c s2c s2s
+step s2b: BEGIN;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1b: BEGIN;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2b s2i s2c s1brr s1merg s2b s2u s1c s2c s2s
+step s2b: BEGIN;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2b s2i s2c s1bs s1merg s2b s2u s1c s2c s2s
+step s2b: BEGIN;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2brr s2i s2c s1b s1merg s2b s2u s1c s2c s2s
+step s2brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1b: BEGIN;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2brr s2i s2c s1brr s1merg s2b s2u s1c s2c s2s
+step s2brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2brr s2i s2c s1bs s1merg s2b s2u s1c s2c s2s
+step s2brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2bs s2i s2c s1b s1merg s2b s2u s1c s2c s2s
+step s2bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1b: BEGIN;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2bs s2i s2c s1brr s1merg s2b s2u s1c s2c s2s
+step s2bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
+
+starting permutation: s2bs s2i s2c s1bs s1merg s2b s2u s1c s2c s2s
+step s2bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s2i: INSERT INTO tpart VALUES (1, 'text01');
+step s2c: COMMIT;
+step s1bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s1merg: ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20;
+step s2b: BEGIN;
+step s2u: UPDATE tpart SET t = 'text01modif' where i = 1; <waiting ...>
+step s1c: COMMIT;
+step s2u: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t          
+--+-----------
+ 5|text05     
+15|text15     
+ 1|text01modif
+25|text25     
+35|text35     
+(5 rows)
+
diff --git a/src/test/isolation/isolation_schedule b/src/test/isolation/isolation_schedule
index 4fc56ae99c..2a98bccbf6 100644
--- a/src/test/isolation/isolation_schedule
+++ b/src/test/isolation/isolation_schedule
@@ -102,6 +102,7 @@ test: partition-key-update-1
 test: partition-key-update-2
 test: partition-key-update-3
 test: partition-key-update-4
+test: partition-merge
 test: plpgsql-toast
 test: cluster-conflict
 test: cluster-conflict-partition
diff --git a/src/test/isolation/specs/partition-merge.spec b/src/test/isolation/specs/partition-merge.spec
new file mode 100644
index 0000000000..ec48732c58
--- /dev/null
+++ b/src/test/isolation/specs/partition-merge.spec
@@ -0,0 +1,54 @@
+# Verify that MERGE operation locks DML operations with partitioned table
+
+setup
+{
+  DROP TABLE IF EXISTS tpart;
+  CREATE TABLE tpart(i int, t text) partition by range(i);
+  CREATE TABLE tpart_00_10 PARTITION OF tpart FOR VALUES FROM (0) TO (10);
+  CREATE TABLE tpart_10_20 PARTITION OF tpart FOR VALUES FROM (10) TO (20);
+  CREATE TABLE tpart_20_30 PARTITION OF tpart FOR VALUES FROM (20) TO (30);
+  CREATE TABLE tpart_default PARTITION OF tpart DEFAULT;
+  INSERT INTO tpart VALUES (5, 'text05');
+  INSERT INTO tpart VALUES (15, 'text15');
+  INSERT INTO tpart VALUES (25, 'text25');
+  INSERT INTO tpart VALUES (35, 'text35');
+}
+
+teardown
+{
+  DROP TABLE tpart;
+}
+
+session s1
+step s1b	{ BEGIN; }
+step s1brr	{ BEGIN ISOLATION LEVEL REPEATABLE READ; }
+step s1bs	{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
+step s1merg	{ ALTER TABLE tpart MERGE PARTITIONS (tpart_00_10, tpart_10_20) INTO tpart_00_20; }
+step s1c	{ COMMIT; }
+
+
+session s2
+step s2b	{ BEGIN; }
+step s2brr	{ BEGIN ISOLATION LEVEL REPEATABLE READ; }
+step s2bs	{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
+step s2i	{ INSERT INTO tpart VALUES (1, 'text01'); }
+step s2u	{ UPDATE tpart SET t = 'text01modif' where i = 1; }
+step s2c	{ COMMIT; }
+step s2s	{ SELECT * FROM tpart; }
+
+
+# s2 inserts row into table. s1 starts MERGE PARTITIONS then
+# s2 trying to update inserted row and waits until s1 finished
+# MERGE operation.
+
+permutation s2b s2i s2c s1b s1merg s2b s2u s1c s2c s2s
+permutation s2b s2i s2c s1brr s1merg s2b s2u s1c s2c s2s
+permutation s2b s2i s2c s1bs s1merg s2b s2u s1c s2c s2s
+
+permutation s2brr s2i s2c s1b s1merg s2b s2u s1c s2c s2s
+permutation s2brr s2i s2c s1brr s1merg s2b s2u s1c s2c s2s
+permutation s2brr s2i s2c s1bs s1merg s2b s2u s1c s2c s2s
+
+permutation s2bs s2i s2c s1b s1merg s2b s2u s1c s2c s2s
+permutation s2bs s2i s2c s1brr s1merg s2b s2u s1c s2c s2s
+permutation s2bs s2i s2c s1bs s1merg s2b s2u s1c s2c s2s
diff --git a/src/test/modules/test_ddl_deparse/test_ddl_deparse.c b/src/test/modules/test_ddl_deparse/test_ddl_deparse.c
index b7c6f98577..b4171dd382 100644
--- a/src/test/modules/test_ddl_deparse/test_ddl_deparse.c
+++ b/src/test/modules/test_ddl_deparse/test_ddl_deparse.c
@@ -297,6 +297,9 @@ get_altertable_subcmdinfo(PG_FUNCTION_ARGS)
 			case AT_DetachPartitionFinalize:
 				strtype = "DETACH PARTITION ... FINALIZE";
 				break;
+			case AT_MergePartitions:
+				strtype = "MERGE PARTITIONS";
+				break;
 			case AT_AddIdentity:
 				strtype = "ADD IDENTITY";
 				break;
diff --git a/src/test/regress/expected/partition_merge.out b/src/test/regress/expected/partition_merge.out
new file mode 100644
index 0000000000..013ab65961
--- /dev/null
+++ b/src/test/regress/expected/partition_merge.out
@@ -0,0 +1,736 @@
+--
+-- PARTITIONS_MERGE
+-- Tests for "ALTER TABLE ... MERGE PARTITIONS ..." command
+--
+CREATE SCHEMA partitions_merge_schema;
+SET search_path = partitions_merge_schema, public;
+--
+-- BY RANGE partitioning
+--
+--
+-- Test for error codes
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_dec2021 PARTITION OF sales_range FOR VALUES FROM ('2021-12-01') TO ('2021-12-31');
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+CREATE TABLE sales_apr2022 (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_apr_1 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-04-15');
+CREATE TABLE sales_apr_2 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-15') TO ('2022-05-01');
+ALTER TABLE sales_range ATTACH PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+-- ERROR:  partition with name "sales_feb2022" already used
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_feb2022) INTO sales_feb_mar_apr2022;
+ERROR:  partition with name "sales_feb2022" already used
+LINE 1: ...e MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_feb2...
+                                                             ^
+-- ERROR:  cannot merge non-table partition "sales_apr2022"
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_apr2022) INTO sales_feb_mar_apr2022;
+ERROR:  cannot merge non-table partition "sales_apr2022"
+-- ERROR:  invalid partitions order, partition "sales_mar2022" can not be merged
+-- (space between sections sales_jan2022 and sales_mar2022)
+ALTER TABLE sales_range MERGE PARTITIONS (sales_jan2022, sales_mar2022) INTO sales_jan_mar2022;
+ERROR:  lower bound of partition "sales_mar2022" conflicts with upper bound of previous partition "sales_jan2022"
+-- ERROR:  invalid partitions order, partition "sales_jan2022" can not be merged
+-- (space between sections sales_dec2021 and sales_jan2022)
+ALTER TABLE sales_range MERGE PARTITIONS (sales_dec2021, sales_jan2022, sales_feb2022) INTO sales_dec_jan_feb2022;
+ERROR:  lower bound of partition "sales_jan2022" conflicts with upper bound of previous partition "sales_dec2021"
+-- NO ERROR: test for custom partitions order
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_jan2022) INTO sales_jan_feb_mar2022;
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+          oid          | relkind | inhdetachpending |                   pg_get_expr                    
+-----------------------+---------+------------------+--------------------------------------------------
+ sales_apr2022         | p       | f                | FOR VALUES FROM ('04-01-2022') TO ('05-01-2022')
+ sales_dec2021         | r       | f                | FOR VALUES FROM ('12-01-2021') TO ('12-31-2021')
+ sales_jan_feb_mar2022 | r       | f                | FOR VALUES FROM ('01-01-2022') TO ('04-01-2022')
+ sales_others          | r       | f                | DEFAULT
+(4 rows)
+
+DROP TABLE sales_range;
+--
+-- Add rows into partitioned table then merge partitions
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+CREATE TABLE sales_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+SELECT pg_catalog.pg_get_partkeydef('sales_range'::regclass);
+ pg_get_partkeydef  
+--------------------
+ RANGE (sales_date)
+(1 row)
+
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+      oid      | relkind | inhdetachpending |                   pg_get_expr                    
+---------------+---------+------------------+--------------------------------------------------
+ sales_apr2022 | r       | f                | FOR VALUES FROM ('04-01-2022') TO ('05-01-2022')
+ sales_feb2022 | r       | f                | FOR VALUES FROM ('02-01-2022') TO ('03-01-2022')
+ sales_jan2022 | r       | f                | FOR VALUES FROM ('01-01-2022') TO ('02-01-2022')
+ sales_mar2022 | r       | f                | FOR VALUES FROM ('03-01-2022') TO ('04-01-2022')
+ sales_others  | r       | f                | DEFAULT
+(5 rows)
+
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_apr2022) INTO sales_feb_mar_apr2022;
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+          oid          | relkind | inhdetachpending |                   pg_get_expr                    
+-----------------------+---------+------------------+--------------------------------------------------
+ sales_feb_mar_apr2022 | r       | f                | FOR VALUES FROM ('02-01-2022') TO ('05-01-2022')
+ sales_jan2022         | r       | f                | FOR VALUES FROM ('01-01-2022') TO ('02-01-2022')
+ sales_others          | r       | f                | DEFAULT
+(3 rows)
+
+SELECT * FROM pg_indexes WHERE tablename = 'sales_feb_mar_apr2022' and schemaname = 'partitions_merge_schema';
+       schemaname        |       tablename       |              indexname               | tablespace |                                                          indexdef                                                           
+-------------------------+-----------------------+--------------------------------------+------------+-----------------------------------------------------------------------------------------------------------------------------
+ partitions_merge_schema | sales_feb_mar_apr2022 | sales_feb_mar_apr2022_sales_date_idx |            | CREATE INDEX sales_feb_mar_apr2022_sales_date_idx ON partitions_merge_schema.sales_feb_mar_apr2022 USING btree (sales_date)
+(1 row)
+
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_jan2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+(3 rows)
+
+SELECT * FROM sales_feb_mar_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(10 rows)
+
+SELECT * FROM sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          14 | Smith         |          510 | 05-04-2022
+(1 row)
+
+-- Use indexscan for test indexes
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+SELECT * FROM sales_feb_mar_apr2022 where sales_date > '2022-01-01';
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+          11 | Trump         |          380 | 04-06-2022
+           5 | Deev          |          250 | 04-07-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+(10 rows)
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+DROP TABLE sales_range;
+--
+-- Merge some partitions into DEFAULT partition
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+CREATE TABLE sales_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+-- Merge partitions (include DEFAULT partition) into partition with the same
+-- name
+ALTER TABLE sales_range MERGE PARTITIONS (sales_jan2022, sales_mar2022, sales_others) INTO sales_others;
+select * from sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+          14 | Smith         |          510 | 05-04-2022
+(7 rows)
+
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+      oid      | relkind | inhdetachpending |                   pg_get_expr                    
+---------------+---------+------------------+--------------------------------------------------
+ sales_apr2022 | r       | f                | FOR VALUES FROM ('04-01-2022') TO ('05-01-2022')
+ sales_feb2022 | r       | f                | FOR VALUES FROM ('02-01-2022') TO ('03-01-2022')
+ sales_others  | r       | f                | DEFAULT
+(3 rows)
+
+DROP TABLE sales_range;
+--
+-- Test for:
+--   * composite partition key;
+--   * GENERATED column;
+--   * column with DEFAULT value.
+--
+CREATE TABLE sales_date (salesman_name VARCHAR(30), sales_year INT, sales_month INT, sales_day INT,
+  sales_date VARCHAR(10) GENERATED ALWAYS AS
+    (LPAD(sales_year::text, 4, '0') || '.' || LPAD(sales_month::text, 2, '0') || '.' || LPAD(sales_day::text, 2, '0')) STORED,
+  sales_department VARCHAR(30) DEFAULT 'Sales department')
+  PARTITION BY RANGE (sales_year, sales_month, sales_day);
+CREATE TABLE sales_dec2022 PARTITION OF sales_date FOR VALUES FROM (2021, 12, 1) TO (2022, 1, 1);
+CREATE TABLE sales_jan2022 PARTITION OF sales_date FOR VALUES FROM (2022, 1, 1) TO (2022, 2, 1);
+CREATE TABLE sales_feb2022 PARTITION OF sales_date FOR VALUES FROM (2022, 2, 1) TO (2022, 3, 1);
+CREATE TABLE sales_other PARTITION OF sales_date FOR VALUES FROM (2022, 3, 1) TO (MAXVALUE, MAXVALUE, MAXVALUE);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2021, 12, 7);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2021, 12, 8);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 1, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 2, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 1, 2);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 2, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 3, 3);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 3, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 5, 1);
+SELECT * FROM sales_date;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(9 rows)
+
+SELECT * FROM sales_dec2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+(2 rows)
+
+SELECT * FROM sales_jan2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+(2 rows)
+
+SELECT * FROM sales_feb2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+(2 rows)
+
+SELECT * FROM sales_other;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(3 rows)
+
+ALTER TABLE sales_date MERGE PARTITIONS (sales_jan2022, sales_feb2022) INTO sales_jan_feb2022;
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 1, 10);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 2, 10);
+SELECT * FROM sales_date;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+ Manager1      |       2022 |           1 |        10 | 2022.01.10 | Sales department
+ Manager2      |       2022 |           2 |        10 | 2022.02.10 | Sales department
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(11 rows)
+
+SELECT * FROM sales_dec2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+(2 rows)
+
+SELECT * FROM sales_jan_feb2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+ Manager1      |       2022 |           1 |        10 | 2022.01.10 | Sales department
+ Manager2      |       2022 |           2 |        10 | 2022.02.10 | Sales department
+(6 rows)
+
+SELECT * FROM sales_other;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(3 rows)
+
+DROP TABLE sales_date;
+--
+-- Test: merge partitions of partitioned table with triggers
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+CREATE TABLE salesmans10_20 PARTITION OF salesmans FOR VALUES FROM (10) TO (20);
+CREATE TABLE salesmans20_30 PARTITION OF salesmans FOR VALUES FROM (20) TO (30);
+CREATE TABLE salesmans30_40 PARTITION OF salesmans FOR VALUES FROM (30) TO (40);
+INSERT INTO salesmans VALUES (1,  'Poirot');
+CREATE OR REPLACE FUNCTION after_insert_row_trigger() RETURNS trigger LANGUAGE 'plpgsql' AS $BODY$
+BEGIN
+	RAISE NOTICE 'trigger(%) called: action = %, when = %, level = %', TG_ARGV[0], TG_OP, TG_WHEN, TG_LEVEL;
+    RETURN NULL;
+END;
+$BODY$;
+CREATE TRIGGER salesmans_after_insert_statement_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+CREATE TRIGGER salesmans_after_insert_row_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH ROW
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (10, 'May');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = STATEMENT
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans10_20 VALUES (19, 'Ivanov');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+ALTER TABLE salesmans MERGE PARTITIONS (salesmans10_20, salesmans20_30, salesmans30_40) INTO salesmans10_40;
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (20, 'Smirnoff');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = STATEMENT
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans10_40 VALUES (30, 'Ford');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+SELECT * FROM salesmans01_10;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+(1 row)
+
+SELECT * FROM salesmans10_40;
+ salesman_id | salesman_name 
+-------------+---------------
+          10 | May
+          19 | Ivanov
+          20 | Smirnoff
+          30 | Ford
+(4 rows)
+
+DROP TABLE salesmans;
+DROP FUNCTION after_insert_row_trigger();
+--
+-- Test: merge partitions with deleted columns
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+-- Create partitions with some deleted columns:
+CREATE TABLE salesmans10_20(d1 VARCHAR(30), salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30));
+CREATE TABLE salesmans20_30(salesman_id INT PRIMARY KEY, d2 INT,  salesman_name VARCHAR(30));
+CREATE TABLE salesmans30_40(salesman_id INT PRIMARY KEY, d3 DATE, salesman_name VARCHAR(30));
+INSERT INTO salesmans10_20 VALUES ('dummy value 1', 19, 'Ivanov');
+INSERT INTO salesmans20_30 VALUES (20, 101, 'Smirnoff');
+INSERT INTO salesmans30_40 VALUES (31, now(), 'Popov');
+ALTER TABLE salesmans10_20 DROP COLUMN d1;
+ALTER TABLE salesmans20_30 DROP COLUMN d2;
+ALTER TABLE salesmans30_40 DROP COLUMN d3;
+ALTER TABLE salesmans ATTACH PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20);
+ALTER TABLE salesmans ATTACH PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30);
+ALTER TABLE salesmans ATTACH PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40);
+INSERT INTO salesmans VALUES (1, 'Poirot');
+INSERT INTO salesmans VALUES (10, 'May');
+INSERT INTO salesmans VALUES (30, 'Ford');
+ALTER TABLE salesmans MERGE PARTITIONS (salesmans10_20, salesmans20_30, salesmans30_40) INTO salesmans10_40;
+select * from salesmans;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+          19 | Ivanov
+          10 | May
+          20 | Smirnoff
+          31 | Popov
+          30 | Ford
+(6 rows)
+
+select * from salesmans01_10;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+(1 row)
+
+select * from salesmans10_40;
+ salesman_id | salesman_name 
+-------------+---------------
+          19 | Ivanov
+          10 | May
+          20 | Smirnoff
+          31 | Popov
+          30 | Ford
+(5 rows)
+
+DROP TABLE salesmans;
+--
+-- Test: merge sub-partitions
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+CREATE TABLE sales_apr2022 (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_apr2022_01_10 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-04-10');
+CREATE TABLE sales_apr2022_10_20 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-10') TO ('2022-04-20');
+CREATE TABLE sales_apr2022_20_30 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-20') TO ('2022-05-01');
+ALTER TABLE sales_range ATTACH PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+(4 rows)
+
+SELECT * FROM sales_apr2022_01_10;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(2 rows)
+
+SELECT * FROM sales_apr2022_10_20;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           4 | Ivanov        |          750 | 04-13-2022
+(1 row)
+
+SELECT * FROM sales_apr2022_20_30;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           3 | Ford          |         2000 | 04-30-2022
+(1 row)
+
+ALTER TABLE sales_apr2022 MERGE PARTITIONS (sales_apr2022_01_10, sales_apr2022_10_20, sales_apr2022_20_30) INTO sales_apr_all;
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+(4 rows)
+
+SELECT * FROM sales_apr_all;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+(4 rows)
+
+DROP TABLE sales_range;
+--
+-- BY LIST partitioning
+--
+--
+-- Test: specific errors for BY LIST partitioning
+--
+CREATE TABLE sales_list
+(salesman_id INT GENERATED ALWAYS AS IDENTITY,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_west PARTITION OF sales_list FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk');
+CREATE TABLE sales_east PARTITION OF sales_list FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok');
+CREATE TABLE sales_central PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+CREATE TABLE sales_list2 (LIKE sales_list) PARTITION BY LIST (sales_state);
+CREATE TABLE sales_nord2 PARTITION OF sales_list2 FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_others2 PARTITION OF sales_list2 DEFAULT;
+CREATE TABLE sales_external (LIKE sales_list);
+CREATE TABLE sales_external2 (vch VARCHAR(5));
+-- ERROR:  partition bound for relation "sales_external" is null
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_east, sales_external) INTO sales_all;
+ERROR:  partition bound for relation "sales_external" is null
+-- ERROR:  partition bound for relation "sales_external2" is null
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_east, sales_external2) INTO sales_all;
+ERROR:  partition bound for relation "sales_external2" is null
+-- ERROR:  relation "sales_nord2" is not a partition of relation "sales_list"
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_nord2, sales_east) INTO sales_all;
+ERROR:  relation "sales_nord2" is not a partition of relation "sales_list"
+DROP TABLE sales_external2;
+DROP TABLE sales_external;
+DROP TABLE sales_list2;
+DROP TABLE sales_list;
+--
+-- Test: BY LIST partitioning, MERGE PARTITIONS with data
+--
+CREATE TABLE sales_list
+(salesman_id INT GENERATED ALWAYS AS IDENTITY,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+CREATE INDEX sales_list_salesman_name_idx ON sales_list USING btree (salesman_name);
+CREATE INDEX sales_list_sales_state_idx ON sales_list USING btree (sales_state);
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_west PARTITION OF sales_list FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk');
+CREATE TABLE sales_east PARTITION OF sales_list FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok');
+CREATE TABLE sales_central PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Trump',    'Magadan',        1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smirnoff', 'Smolensk',       500,  '2022-03-03');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ford',     'St. Petersburg', 2000, '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ivanov',   'Moscow',         750,  '2022-03-04');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Deev',     'Voronezh',       250,  '2022-03-07');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Poirot',   'Kazan',          1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-06');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Li',       'Vladivostok',    1150, '2022-03-09');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-11');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Halder',   'Murmansk',       800,  '2022-03-02');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Muller',   'Bryansk',        650,  '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smith',    'Volgograd',      350,  '2022-03-10');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Gandi',    'Moscow',         150,  '2022-03-08');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Plato',    'Voronezh',       950,  '2022-03-05');
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_list'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+      oid      | relkind | inhdetachpending |                      pg_get_expr                       
+---------------+---------+------------------+--------------------------------------------------------
+ sales_central | r       | f                | FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd')
+ sales_east    | r       | f                | FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok')
+ sales_nord    | r       | f                | FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta')
+ sales_west    | r       | f                | FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk')
+ sales_others  | r       | f                | DEFAULT
+(5 rows)
+
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_east, sales_central) INTO sales_all;
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_list'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+     oid      | relkind | inhdetachpending |                                                        pg_get_expr                                                        
+--------------+---------+------------------+---------------------------------------------------------------------------------------------------------------------------
+ sales_all    | r       | f                | FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk', 'Magadan', 'Khabarovsk', 'Vladivostok', 'Moscow', 'Kazan', 'Volgograd')
+ sales_nord   | r       | f                | FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta')
+ sales_others | r       | f                | DEFAULT
+(3 rows)
+
+SELECT * FROM sales_list;
+ salesman_id | salesman_name |  sales_state   | sales_amount | sales_date 
+-------------+---------------+----------------+--------------+------------
+           2 | Smirnoff      | Smolensk       |          500 | 03-03-2022
+           5 | Deev          | Voronezh       |          250 | 03-07-2022
+          11 | Muller        | Bryansk        |          650 | 03-05-2022
+          14 | Plato         | Voronezh       |          950 | 03-05-2022
+           1 | Trump         | Magadan        |         1000 | 03-01-2022
+           8 | Li            | Vladivostok    |         1150 | 03-09-2022
+           4 | Ivanov        | Moscow         |          750 | 03-04-2022
+           6 | Poirot        | Kazan          |         1000 | 03-01-2022
+          12 | Smith         | Volgograd      |          350 | 03-10-2022
+          13 | Gandi         | Moscow         |          150 | 03-08-2022
+           3 | Ford          | St. Petersburg |         2000 | 03-05-2022
+           7 | May           | Ukhta          |         1200 | 03-06-2022
+           9 | May           | Ukhta          |         1200 | 03-11-2022
+          10 | Halder        | Murmansk       |          800 | 03-02-2022
+(14 rows)
+
+SELECT * FROM sales_nord;
+ salesman_id | salesman_name |  sales_state   | sales_amount | sales_date 
+-------------+---------------+----------------+--------------+------------
+           3 | Ford          | St. Petersburg |         2000 | 03-05-2022
+           7 | May           | Ukhta          |         1200 | 03-06-2022
+           9 | May           | Ukhta          |         1200 | 03-11-2022
+          10 | Halder        | Murmansk       |          800 | 03-02-2022
+(4 rows)
+
+SELECT * FROM sales_all;
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           2 | Smirnoff      | Smolensk    |          500 | 03-03-2022
+           5 | Deev          | Voronezh    |          250 | 03-07-2022
+          11 | Muller        | Bryansk     |          650 | 03-05-2022
+          14 | Plato         | Voronezh    |          950 | 03-05-2022
+           1 | Trump         | Magadan     |         1000 | 03-01-2022
+           8 | Li            | Vladivostok |         1150 | 03-09-2022
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+           6 | Poirot        | Kazan       |         1000 | 03-01-2022
+          12 | Smith         | Volgograd   |          350 | 03-10-2022
+          13 | Gandi         | Moscow      |          150 | 03-08-2022
+(10 rows)
+
+-- Use indexscan for test indexes after merge partitions
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+SELECT * FROM sales_all WHERE sales_state = 'Moscow';
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+          13 | Gandi         | Moscow      |          150 | 03-08-2022
+(2 rows)
+
+SELECT * FROM sales_list WHERE sales_state = 'Moscow';
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+          13 | Gandi         | Moscow      |          150 | 03-08-2022
+(2 rows)
+
+SELECT * FROM sales_list WHERE salesman_name = 'Ivanov';
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+(1 row)
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+DROP TABLE sales_list;
+--
+DROP SCHEMA partitions_merge_schema;
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index 15e015b3d6..41fa8e93c5 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -119,7 +119,7 @@ test: plancache limit plpgsql copy2 temp domain rangefuncs prepare conversion tr
 # The stats test resets stats, so nothing else needing stats access can be in
 # this group.
 # ----------
-test: partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats
+test: partition_merge partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats
 
 # event_trigger cannot run concurrently with any test that runs DDL
 # oidjoins is read-only, though, and should run late for best coverage
diff --git a/src/test/regress/sql/partition_merge.sql b/src/test/regress/sql/partition_merge.sql
new file mode 100644
index 0000000000..8bf90fd621
--- /dev/null
+++ b/src/test/regress/sql/partition_merge.sql
@@ -0,0 +1,434 @@
+--
+-- PARTITIONS_MERGE
+-- Tests for "ALTER TABLE ... MERGE PARTITIONS ..." command
+--
+
+CREATE SCHEMA partitions_merge_schema;
+SET search_path = partitions_merge_schema, public;
+
+--
+-- BY RANGE partitioning
+--
+
+--
+-- Test for error codes
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_dec2021 PARTITION OF sales_range FOR VALUES FROM ('2021-12-01') TO ('2021-12-31');
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+
+CREATE TABLE sales_apr2022 (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_apr_1 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-04-15');
+CREATE TABLE sales_apr_2 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-15') TO ('2022-05-01');
+ALTER TABLE sales_range ATTACH PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+-- ERROR:  partition with name "sales_feb2022" already used
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_feb2022) INTO sales_feb_mar_apr2022;
+-- ERROR:  cannot merge non-table partition "sales_apr2022"
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_apr2022) INTO sales_feb_mar_apr2022;
+-- ERROR:  invalid partitions order, partition "sales_mar2022" can not be merged
+-- (space between sections sales_jan2022 and sales_mar2022)
+ALTER TABLE sales_range MERGE PARTITIONS (sales_jan2022, sales_mar2022) INTO sales_jan_mar2022;
+-- ERROR:  invalid partitions order, partition "sales_jan2022" can not be merged
+-- (space between sections sales_dec2021 and sales_jan2022)
+ALTER TABLE sales_range MERGE PARTITIONS (sales_dec2021, sales_jan2022, sales_feb2022) INTO sales_dec_jan_feb2022;
+
+-- NO ERROR: test for custom partitions order
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_jan2022) INTO sales_jan_feb_mar2022;
+
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+
+DROP TABLE sales_range;
+
+--
+-- Add rows into partitioned table then merge partitions
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+CREATE TABLE sales_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+SELECT pg_catalog.pg_get_partkeydef('sales_range'::regclass);
+
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+
+ALTER TABLE sales_range MERGE PARTITIONS (sales_feb2022, sales_mar2022, sales_apr2022) INTO sales_feb_mar_apr2022;
+
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+
+SELECT * FROM pg_indexes WHERE tablename = 'sales_feb_mar_apr2022' and schemaname = 'partitions_merge_schema';
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_jan2022;
+SELECT * FROM sales_feb_mar_apr2022;
+SELECT * FROM sales_others;
+
+-- Use indexscan for test indexes
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+
+SELECT * FROM sales_feb_mar_apr2022 where sales_date > '2022-01-01';
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+
+DROP TABLE sales_range;
+
+--
+-- Merge some partitions into DEFAULT partition
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+CREATE TABLE sales_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+-- Merge partitions (include DEFAULT partition) into partition with the same
+-- name
+ALTER TABLE sales_range MERGE PARTITIONS (sales_jan2022, sales_mar2022, sales_others) INTO sales_others;
+
+select * from sales_others;
+
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_range'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+
+DROP TABLE sales_range;
+
+--
+-- Test for:
+--   * composite partition key;
+--   * GENERATED column;
+--   * column with DEFAULT value.
+--
+CREATE TABLE sales_date (salesman_name VARCHAR(30), sales_year INT, sales_month INT, sales_day INT,
+  sales_date VARCHAR(10) GENERATED ALWAYS AS
+    (LPAD(sales_year::text, 4, '0') || '.' || LPAD(sales_month::text, 2, '0') || '.' || LPAD(sales_day::text, 2, '0')) STORED,
+  sales_department VARCHAR(30) DEFAULT 'Sales department')
+  PARTITION BY RANGE (sales_year, sales_month, sales_day);
+
+CREATE TABLE sales_dec2022 PARTITION OF sales_date FOR VALUES FROM (2021, 12, 1) TO (2022, 1, 1);
+CREATE TABLE sales_jan2022 PARTITION OF sales_date FOR VALUES FROM (2022, 1, 1) TO (2022, 2, 1);
+CREATE TABLE sales_feb2022 PARTITION OF sales_date FOR VALUES FROM (2022, 2, 1) TO (2022, 3, 1);
+CREATE TABLE sales_other PARTITION OF sales_date FOR VALUES FROM (2022, 3, 1) TO (MAXVALUE, MAXVALUE, MAXVALUE);
+
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2021, 12, 7);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2021, 12, 8);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 1, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 2, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 1, 2);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 2, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 3, 3);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 3, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 5, 1);
+
+SELECT * FROM sales_date;
+SELECT * FROM sales_dec2022;
+SELECT * FROM sales_jan2022;
+SELECT * FROM sales_feb2022;
+SELECT * FROM sales_other;
+
+ALTER TABLE sales_date MERGE PARTITIONS (sales_jan2022, sales_feb2022) INTO sales_jan_feb2022;
+
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 1, 10);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 2, 10);
+
+SELECT * FROM sales_date;
+SELECT * FROM sales_dec2022;
+SELECT * FROM sales_jan_feb2022;
+SELECT * FROM sales_other;
+
+DROP TABLE sales_date;
+
+--
+-- Test: merge partitions of partitioned table with triggers
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+CREATE TABLE salesmans10_20 PARTITION OF salesmans FOR VALUES FROM (10) TO (20);
+CREATE TABLE salesmans20_30 PARTITION OF salesmans FOR VALUES FROM (20) TO (30);
+CREATE TABLE salesmans30_40 PARTITION OF salesmans FOR VALUES FROM (30) TO (40);
+
+INSERT INTO salesmans VALUES (1,  'Poirot');
+
+CREATE OR REPLACE FUNCTION after_insert_row_trigger() RETURNS trigger LANGUAGE 'plpgsql' AS $BODY$
+BEGIN
+	RAISE NOTICE 'trigger(%) called: action = %, when = %, level = %', TG_ARGV[0], TG_OP, TG_WHEN, TG_LEVEL;
+    RETURN NULL;
+END;
+$BODY$;
+
+CREATE TRIGGER salesmans_after_insert_statement_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+
+CREATE TRIGGER salesmans_after_insert_row_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH ROW
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (10, 'May');
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans10_20 VALUES (19, 'Ivanov');
+
+ALTER TABLE salesmans MERGE PARTITIONS (salesmans10_20, salesmans20_30, salesmans30_40) INTO salesmans10_40;
+
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (20, 'Smirnoff');
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans10_40 VALUES (30, 'Ford');
+
+SELECT * FROM salesmans01_10;
+SELECT * FROM salesmans10_40;
+
+DROP TABLE salesmans;
+DROP FUNCTION after_insert_row_trigger();
+
+--
+-- Test: merge partitions with deleted columns
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+-- Create partitions with some deleted columns:
+CREATE TABLE salesmans10_20(d1 VARCHAR(30), salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30));
+CREATE TABLE salesmans20_30(salesman_id INT PRIMARY KEY, d2 INT,  salesman_name VARCHAR(30));
+CREATE TABLE salesmans30_40(salesman_id INT PRIMARY KEY, d3 DATE, salesman_name VARCHAR(30));
+
+INSERT INTO salesmans10_20 VALUES ('dummy value 1', 19, 'Ivanov');
+INSERT INTO salesmans20_30 VALUES (20, 101, 'Smirnoff');
+INSERT INTO salesmans30_40 VALUES (31, now(), 'Popov');
+
+ALTER TABLE salesmans10_20 DROP COLUMN d1;
+ALTER TABLE salesmans20_30 DROP COLUMN d2;
+ALTER TABLE salesmans30_40 DROP COLUMN d3;
+
+ALTER TABLE salesmans ATTACH PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20);
+ALTER TABLE salesmans ATTACH PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30);
+ALTER TABLE salesmans ATTACH PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40);
+
+INSERT INTO salesmans VALUES (1, 'Poirot');
+INSERT INTO salesmans VALUES (10, 'May');
+INSERT INTO salesmans VALUES (30, 'Ford');
+
+ALTER TABLE salesmans MERGE PARTITIONS (salesmans10_20, salesmans20_30, salesmans30_40) INTO salesmans10_40;
+
+select * from salesmans;
+select * from salesmans01_10;
+select * from salesmans10_40;
+
+DROP TABLE salesmans;
+
+--
+-- Test: merge sub-partitions
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+
+CREATE TABLE sales_apr2022 (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_apr2022_01_10 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-04-10');
+CREATE TABLE sales_apr2022_10_20 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-10') TO ('2022-04-20');
+CREATE TABLE sales_apr2022_20_30 PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-20') TO ('2022-05-01');
+ALTER TABLE sales_range ATTACH PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_apr2022;
+SELECT * FROM sales_apr2022_01_10;
+SELECT * FROM sales_apr2022_10_20;
+SELECT * FROM sales_apr2022_20_30;
+
+ALTER TABLE sales_apr2022 MERGE PARTITIONS (sales_apr2022_01_10, sales_apr2022_10_20, sales_apr2022_20_30) INTO sales_apr_all;
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_apr2022;
+SELECT * FROM sales_apr_all;
+
+DROP TABLE sales_range;
+
+--
+-- BY LIST partitioning
+--
+
+--
+-- Test: specific errors for BY LIST partitioning
+--
+CREATE TABLE sales_list
+(salesman_id INT GENERATED ALWAYS AS IDENTITY,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_west PARTITION OF sales_list FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk');
+CREATE TABLE sales_east PARTITION OF sales_list FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok');
+CREATE TABLE sales_central PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+
+
+CREATE TABLE sales_list2 (LIKE sales_list) PARTITION BY LIST (sales_state);
+CREATE TABLE sales_nord2 PARTITION OF sales_list2 FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_others2 PARTITION OF sales_list2 DEFAULT;
+
+
+CREATE TABLE sales_external (LIKE sales_list);
+CREATE TABLE sales_external2 (vch VARCHAR(5));
+
+-- ERROR:  partition bound for relation "sales_external" is null
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_east, sales_external) INTO sales_all;
+-- ERROR:  partition bound for relation "sales_external2" is null
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_east, sales_external2) INTO sales_all;
+-- ERROR:  relation "sales_nord2" is not a partition of relation "sales_list"
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_nord2, sales_east) INTO sales_all;
+
+DROP TABLE sales_external2;
+DROP TABLE sales_external;
+DROP TABLE sales_list2;
+DROP TABLE sales_list;
+
+--
+-- Test: BY LIST partitioning, MERGE PARTITIONS with data
+--
+CREATE TABLE sales_list
+(salesman_id INT GENERATED ALWAYS AS IDENTITY,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+
+CREATE INDEX sales_list_salesman_name_idx ON sales_list USING btree (salesman_name);
+CREATE INDEX sales_list_sales_state_idx ON sales_list USING btree (sales_state);
+
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_west PARTITION OF sales_list FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk');
+CREATE TABLE sales_east PARTITION OF sales_list FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok');
+CREATE TABLE sales_central PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Trump',    'Magadan',        1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smirnoff', 'Smolensk',       500,  '2022-03-03');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ford',     'St. Petersburg', 2000, '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ivanov',   'Moscow',         750,  '2022-03-04');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Deev',     'Voronezh',       250,  '2022-03-07');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Poirot',   'Kazan',          1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-06');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Li',       'Vladivostok',    1150, '2022-03-09');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-11');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Halder',   'Murmansk',       800,  '2022-03-02');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Muller',   'Bryansk',        650,  '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smith',    'Volgograd',      350,  '2022-03-10');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Gandi',    'Moscow',         150,  '2022-03-08');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Plato',    'Voronezh',       950,  '2022-03-05');
+
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_list'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_east, sales_central) INTO sales_all;
+
+-- show partitions with conditions:
+SELECT c.oid::pg_catalog.regclass, c.relkind, inhdetachpending, pg_catalog.pg_get_expr(c.relpartbound, c.oid)
+  FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i
+  WHERE c.oid = i.inhrelid AND i.inhparent = 'sales_list'::regclass
+  ORDER BY pg_catalog.pg_get_expr(c.relpartbound, c.oid) = 'DEFAULT', c.oid::pg_catalog.regclass::pg_catalog.text;
+
+SELECT * FROM sales_list;
+SELECT * FROM sales_nord;
+SELECT * FROM sales_all;
+
+-- Use indexscan for test indexes after merge partitions
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+
+SELECT * FROM sales_all WHERE sales_state = 'Moscow';
+SELECT * FROM sales_list WHERE sales_state = 'Moscow';
+SELECT * FROM sales_list WHERE salesman_name = 'Ivanov';
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+
+DROP TABLE sales_list;
+
+--
+DROP SCHEMA partitions_merge_schema;
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 0b7bc45767..8775bf37d3 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -2534,6 +2534,7 @@ SimpleStats
 SimpleStringList
 SimpleStringListCell
 SingleBoundSortItem
+SinglePartitionSpec
 Size
 SkipPages
 SlabBlock
-- 
2.31.0.windows.1

From 309944461a902ae5aea8e229991c093de6c36ffc Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 17:58:52 +0300
Subject: [PATCH v17 2/3] ALTER TABLE SPLIT PARTITION command

---
 src/backend/commands/tablecmds.c              |  407 +++++
 src/backend/parser/gram.y                     |   38 +-
 src/backend/parser/parse_utilcmd.c            |   62 +-
 src/backend/partitioning/partbounds.c         |  655 ++++++++
 src/backend/utils/adt/ruleutils.c             |   18 +
 src/include/nodes/parsenodes.h                |    1 +
 src/include/parser/kwlist.h                   |    1 +
 src/include/partitioning/partbounds.h         |    5 +
 src/include/utils/ruleutils.h                 |    2 +
 .../isolation/expected/partition-split.out    |  190 +++
 src/test/isolation/isolation_schedule         |    1 +
 src/test/isolation/specs/partition-split.spec |   54 +
 .../test_ddl_deparse/test_ddl_deparse.c       |    3 +
 src/test/regress/expected/partition_split.out | 1417 +++++++++++++++++
 src/test/regress/parallel_schedule            |    2 +-
 src/test/regress/sql/partition_split.sql      |  833 ++++++++++
 16 files changed, 3677 insertions(+), 12 deletions(-)
 create mode 100644 src/test/isolation/expected/partition-split.out
 create mode 100644 src/test/isolation/specs/partition-split.spec
 create mode 100644 src/test/regress/expected/partition_split.out
 create mode 100644 src/test/regress/sql/partition_split.sql

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 49e9340d5c..29c29e9d52 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -638,6 +638,9 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);
 
+static void ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab,
+								 Relation rel, PartitionCmd *cmd,
+								 AlterTableUtilityContext *context);
 static void ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel,
 								  PartitionCmd *cmd, AlterTableUtilityContext *context);
 
@@ -4478,6 +4481,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
+			case AT_SplitPartition:
+				cmd_lockmode = AccessExclusiveLock;
+				break;
+
 			case AT_MergePartitions:
 				cmd_lockmode = AccessExclusiveLock;
 				break;
@@ -4903,6 +4910,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			/* No command-specific prep needed */
 			pass = AT_PASS_MISC;
 			break;
+		case AT_SplitPartition:
+			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
+			/* No command-specific prep needed */
+			pass = AT_PASS_MISC;
+			break;
 		case AT_MergePartitions:
 			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
 			/* No command-specific prep needed */
@@ -5295,6 +5307,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
 		case AT_DetachPartitionFinalize:
 			address = ATExecDetachPartitionFinalize(rel, ((PartitionCmd *) cmd->def)->name);
 			break;
+		case AT_SplitPartition:
+			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
+									  cur_pass, context);
+			Assert(cmd != NULL);
+			Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
+			ATExecSplitPartition(wqueue, tab, rel, (PartitionCmd *) cmd->def,
+								 context);
+			break;
 		case AT_MergePartitions:
 			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
 									  cur_pass, context);
@@ -6286,6 +6306,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
 			return "DETACH PARTITION";
 		case AT_DetachPartitionFinalize:
 			return "DETACH PARTITION ... FINALIZE";
+		case AT_SplitPartition:
+			return "SPLIT PARTITION";
 		case AT_MergePartitions:
 			return "MERGE PARTITIONS";
 		case AT_AddIdentity:
@@ -19426,6 +19448,255 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 	return cstorage;
 }
 
+/*
+ * Struct with context of new partition for insert rows from splited partition
+ */
+typedef struct SplitPartitionContext
+{
+	ExprState  *partqualstate;	/* expression for check slot for partition
+								 * (NULL for DEFAULT partition) */
+	BulkInsertState bistate;	/* state of bulk inserts for partition */
+	TupleTableSlot *dstslot;	/* slot for insert row into partition */
+	Relation	partRel;		/* relation for partition */
+}			SplitPartitionContext;
+
+
+/*
+ * createSplitPartitionContext: create context for partition and fill it
+ */
+static SplitPartitionContext *
+createSplitPartitionContext(Relation partRel)
+{
+	SplitPartitionContext *pc;
+
+	pc = (SplitPartitionContext *) palloc0(sizeof(SplitPartitionContext));
+	pc->partRel = partRel;
+
+	/*
+	 * Prepare a BulkInsertState for table_tuple_insert. The FSM is empty, so
+	 * don't bother using it.
+	 */
+	pc->bistate = GetBulkInsertState();
+
+	/* Create tuple slot for new partition. */
+	pc->dstslot = MakeSingleTupleTableSlot(RelationGetDescr(pc->partRel),
+										   table_slot_callbacks(pc->partRel));
+	ExecStoreAllNullTuple(pc->dstslot);
+
+	return pc;
+}
+
+/*
+ * deleteSplitPartitionContext: delete context for partition
+ */
+static void
+deleteSplitPartitionContext(SplitPartitionContext * pc, int ti_options)
+{
+	ExecDropSingleTupleTableSlot(pc->dstslot);
+	FreeBulkInsertState(pc->bistate);
+
+	table_finish_bulk_insert(pc->partRel, ti_options);
+
+	pfree(pc);
+}
+
+/*
+ * moveSplitTableRows: scan split partition (splitRel) of partitioned table
+ * (rel) and move rows into new partitions.
+ *
+ * New partitions description:
+ * partlist: list of pointers to SinglePartitionSpec structures.
+ * newPartRels: list of Relation's.
+ * defaultPartOid: oid of DEFAULT partition, for table rel.
+ */
+static void
+moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPartRels, Oid defaultPartOid)
+{
+	/* The FSM is empty, so don't bother using it. */
+	int			ti_options = TABLE_INSERT_SKIP_FSM;
+	CommandId	mycid;
+	EState	   *estate;
+	ListCell   *listptr,
+			   *listptr2;
+	TupleTableSlot *srcslot;
+	ExprContext *econtext;
+	TableScanDesc scan;
+	Snapshot	snapshot;
+	MemoryContext oldCxt;
+	List	   *partContexts = NIL;
+	TupleConversionMap *tuple_map;
+	SplitPartitionContext *defaultPartCtx = NULL,
+			   *pc;
+	bool		isOldDefaultPart = false;
+
+	mycid = GetCurrentCommandId(true);
+
+	estate = CreateExecutorState();
+
+	forboth(listptr, partlist, listptr2, newPartRels)
+	{
+		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
+
+		pc = createSplitPartitionContext((Relation) lfirst(listptr2));
+
+		if (sps->bound->is_default)
+		{
+			/* We should not create constraint for detached DEFAULT partition. */
+			defaultPartCtx = pc;
+		}
+		else
+		{
+			List	   *partConstraint;
+
+			/* Build expression execution states for partition check quals. */
+			partConstraint = get_qual_from_partbound(rel, sps->bound);
+			partConstraint =
+				(List *) eval_const_expressions(NULL,
+												(Node *) partConstraint);
+			/* Make boolean expression for ExecCheck(). */
+			partConstraint = list_make1(make_ands_explicit(partConstraint));
+
+			/*
+			 * Map the vars in the constraint expression from rel's attnos to
+			 * splitRel's.
+			 */
+			partConstraint = map_partition_varattnos(partConstraint,
+													 1, splitRel, rel);
+
+			pc->partqualstate =
+				ExecPrepareExpr((Expr *) linitial(partConstraint), estate);
+			Assert(pc->partqualstate != NULL);
+		}
+
+		/* Store partition context into list. */
+		partContexts = lappend(partContexts, pc);
+	}
+
+	/*
+	 * Create partition context for DEFAULT partition. We can insert values
+	 * into this partition in case spaces with values between new partitions.
+	 */
+	if (!defaultPartCtx && OidIsValid(defaultPartOid))
+	{
+		/* Indicate that we allocate context for old DEFAULT partition */
+		isOldDefaultPart = true;
+		defaultPartCtx = createSplitPartitionContext(table_open(defaultPartOid, AccessExclusiveLock));
+	}
+
+	econtext = GetPerTupleExprContext(estate);
+
+	/* Create necessary tuple slot. */
+	srcslot = MakeSingleTupleTableSlot(RelationGetDescr(splitRel),
+									   table_slot_callbacks(splitRel));
+
+	/*
+	 * Map computing for moving attributes of split partition to new partition
+	 * (for first new partition but other new partitions can use the same
+	 * map).
+	 */
+	pc = (SplitPartitionContext *) lfirst(list_head(partContexts));
+	tuple_map = convert_tuples_by_name(RelationGetDescr(splitRel),
+									   RelationGetDescr(pc->partRel));
+
+	/* Scan through the rows. */
+	snapshot = RegisterSnapshot(GetLatestSnapshot());
+	scan = table_beginscan(splitRel, snapshot, 0, NULL);
+
+	/*
+	 * Switch to per-tuple memory context and reset it for each tuple
+	 * produced, so we don't leak memory.
+	 */
+	oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
+
+	while (table_scan_getnextslot(scan, ForwardScanDirection, srcslot))
+	{
+		bool		found = false;
+		TupleTableSlot *insertslot;
+
+		/* Extract data from old tuple. */
+		slot_getallattrs(srcslot);
+
+		econtext->ecxt_scantuple = srcslot;
+
+		/* Search partition for current slot srcslot. */
+		foreach(listptr, partContexts)
+		{
+			pc = (SplitPartitionContext *) lfirst(listptr);
+
+			if (pc->partqualstate /* skip DEFAULT partition */ &&
+				ExecCheck(pc->partqualstate, econtext))
+			{
+				found = true;
+				break;
+			}
+			ResetExprContext(econtext);
+		}
+		if (!found)
+		{
+			/* Use DEFAULT partition if it exists. */
+			if (defaultPartCtx)
+				pc = defaultPartCtx;
+			else
+				ereport(ERROR,
+						(errcode(ERRCODE_CHECK_VIOLATION),
+						 errmsg("can not find partition for split partition row"),
+						 errtable(splitRel)));
+		}
+
+		if (tuple_map)
+		{
+			/* Need to use map for copy attributes. */
+			insertslot = execute_attr_map_slot(tuple_map->attrMap, srcslot, pc->dstslot);
+		}
+		else
+		{
+			/* Copy attributes directly. */
+			insertslot = pc->dstslot;
+
+			ExecClearTuple(insertslot);
+
+			memcpy(insertslot->tts_values, srcslot->tts_values,
+				   sizeof(Datum) * srcslot->tts_nvalid);
+			memcpy(insertslot->tts_isnull, srcslot->tts_isnull,
+				   sizeof(bool) * srcslot->tts_nvalid);
+
+			ExecStoreVirtualTuple(insertslot);
+		}
+
+		/* Write the tuple out to the new relation. */
+		table_tuple_insert(pc->partRel, insertslot, mycid, ti_options, pc->bistate);
+
+		ResetExprContext(econtext);
+
+		CHECK_FOR_INTERRUPTS();
+	}
+
+	MemoryContextSwitchTo(oldCxt);
+
+	table_endscan(scan);
+	UnregisterSnapshot(snapshot);
+
+	if (tuple_map)
+		free_conversion_map(tuple_map);
+
+	ExecDropSingleTupleTableSlot(srcslot);
+
+	FreeExecutorState(estate);
+
+	foreach(listptr, partContexts)
+		deleteSplitPartitionContext((SplitPartitionContext *) lfirst(listptr), ti_options);
+
+	/* Need to close table and free buffers for DEFAULT partition. */
+	if (isOldDefaultPart)
+	{
+		Relation defaultPartRel = defaultPartCtx->partRel;
+
+		deleteSplitPartitionContext(defaultPartCtx, ti_options);
+		/* Keep the lock until commit. */
+		table_close(defaultPartRel, NoLock);
+	}
+}
+
 /*
  * createPartitionTable: create table for new partition with given name
  * (newPartName) like table (modelRelName)
@@ -19480,6 +19751,142 @@ createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
 				   NULL);
 }
 
+/*
+ * ALTER TABLE <name> SPLIT PARTITION <partition-name> INTO <partition-list>
+ */
+static void
+ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
+					 PartitionCmd *cmd, AlterTableUtilityContext *context)
+{
+	Relation	splitRel;
+	Oid			splitRelOid;
+	char		relname[NAMEDATALEN];
+	Oid			namespaceId;
+	ListCell   *listptr,
+			   *listptr2;
+	bool		isSameName = false;
+	char		tmpRelName[NAMEDATALEN];
+	List	   *newPartRels = NIL;
+	ObjectAddress object;
+	RangeVar   *splitPartName = cmd->name;
+	Oid			defaultPartOid;
+
+	defaultPartOid = get_default_oid_from_partdesc(RelationGetPartitionDesc(rel, true));
+
+	/*
+	 * We are going to detach and remove this partition: need to use exclusive
+	 * lock for prevent DML-queries to the partition.
+	 */
+	splitRel = table_openrv(splitPartName, AccessExclusiveLock);
+
+	if (splitRel->rd_rel->relkind != RELKIND_RELATION)
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("cannot split non-table partition \"%s\"",
+						RelationGetRelationName(splitRel))));
+
+	splitRelOid = RelationGetRelid(splitRel);
+
+	/* Check descriptions of new partitions. */
+	foreach(listptr, cmd->partlist)
+	{
+		Oid			existing_relid;
+		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
+
+		strlcpy(relname, sps->name->relname, NAMEDATALEN);
+
+		/*
+		 * Look up the namespace in which we are supposed to create the
+		 * partition, check we have permission to create there, lock it
+		 * against concurrent drop, and mark stmt->relation as
+		 * RELPERSISTENCE_TEMP if a temporary namespace is selected.
+		 */
+		namespaceId =
+			RangeVarGetAndCheckCreationNamespace(sps->name, NoLock, NULL);
+
+		/*
+		 * This would fail later on anyway, if the relation already exists.
+		 * But by catching it here we can emit a nicer error message.
+		 */
+		existing_relid = get_relname_relid(relname, namespaceId);
+		if (existing_relid == splitRelOid && !isSameName)
+			/* One new partition can have the same name as split partition. */
+			isSameName = true;
+		else if (existing_relid != InvalidOid)
+			ereport(ERROR,
+					(errcode(ERRCODE_DUPLICATE_TABLE),
+					 errmsg("relation \"%s\" already exists", relname)));
+	}
+
+	/* Detach split partition. */
+	RemoveInheritance(splitRel, rel, false);
+	/* Do the final part of detaching. */
+	DetachPartitionFinalize(rel, splitRel, false, defaultPartOid);
+
+	/*
+	 * If new partition has the same name as split partition then we should
+	 * rename split partition for reuse name.
+	 */
+	if (isSameName)
+	{
+		/*
+		 * We must bump the command counter to make the split partition tuple
+		 * visible for rename.
+		 */
+		CommandCounterIncrement();
+		/* Rename partition. */
+		sprintf(tmpRelName, "split-%u-%X-tmp", RelationGetRelid(rel), MyProcPid);
+		RenameRelationInternal(splitRelOid, tmpRelName, false, false);
+		splitPartName = makeRangeVar(
+									 get_namespace_name(RelationGetNamespace(splitRel)),
+									 tmpRelName, -1);
+
+		/*
+		 * We must bump the command counter to make the split partition tuple
+		 * visible after rename.
+		 */
+		CommandCounterIncrement();
+	}
+
+	/* Create new partitions (like split partition), without indexes. */
+	foreach(listptr, cmd->partlist)
+	{
+		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
+		Relation	newPartRel;
+
+		createPartitionTable(sps->name, splitPartName, context);
+
+		/* Open the new partition and acquire exclusive lock on it. */
+		newPartRel = table_openrv(sps->name, AccessExclusiveLock);
+
+		newPartRels = lappend(newPartRels, newPartRel);
+	}
+
+	/* Copy data from split partition to new partitions. */
+	moveSplitTableRows(rel, splitRel, cmd->partlist, newPartRels, defaultPartOid);
+	/* Keep the lock until commit. */
+	table_close(splitRel, NoLock);
+
+	/* Attach new partitions to partitioned table. */
+	forboth(listptr, cmd->partlist, listptr2, newPartRels)
+	{
+		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
+		Relation	newPartRel = (Relation) lfirst(listptr2);
+
+		/* wqueue = NULL: verification for each cloned constraint is not need. */
+		attachPartitionTable(NULL, rel, newPartRel, sps->bound);
+		/* Keep the lock until commit. */
+		table_close(newPartRel, NoLock);
+	}
+
+	/* Drop split partition. */
+	object.classId = RelationRelationId;
+	object.objectId = splitRelOid;
+	object.objectSubId = 0;
+	/* Probably DROP_CASCADE is not needed. */
+	performDeletion(&object, DROP_RESTRICT, 0);
+}
+
 /*
  * Struct with context of merged partition
  */
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index ad8f68b99d..737b97445d 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -268,6 +268,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	PartitionElem *partelem;
 	PartitionSpec *partspec;
 	PartitionBoundSpec *partboundspec;
+	SinglePartitionSpec *singlepartspec;
 	RoleSpec   *rolespec;
 	PublicationObjSpec *publicationobjectspec;
 	struct SelectLimit *selectlimit;
@@ -640,6 +641,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 %type <partelem>	part_elem
 %type <list>		part_params
 %type <partboundspec> PartitionBoundSpec
+%type <singlepartspec>	SinglePartitionSpec
+%type <list>		partitions_list
 %type <list>		hash_partbound
 %type <defelt>		hash_partbound_elem
 
@@ -740,7 +743,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
 	SAVEPOINT SCHEMA SCHEMAS SCROLL SEARCH SECOND_P SECURITY SELECT SEQUENCE SEQUENCES
 	SERIALIZABLE SERVER SESSION SESSION_USER SET SETS SETOF SHARE SHOW
-	SIMILAR SIMPLE SKIP SMALLINT SNAPSHOT SOME SQL_P STABLE STANDALONE_P
+	SIMILAR SIMPLE SKIP SMALLINT SNAPSHOT SOME SPLIT SQL_P STABLE STANDALONE_P
 	START STATEMENT STATISTICS STDIN STDOUT STORAGE STORED STRICT_P STRIP_P
 	SUBSCRIPTION SUBSTRING SUPPORT SYMMETRIC SYSID SYSTEM_P SYSTEM_USER
 
@@ -2270,6 +2273,23 @@ alter_table_cmds:
 			| alter_table_cmds ',' alter_table_cmd	{ $$ = lappend($1, $3); }
 		;
 
+partitions_list:
+			SinglePartitionSpec							{ $$ = list_make1($1); }
+			| partitions_list ',' SinglePartitionSpec	{ $$ = lappend($1, $3); }
+		;
+
+SinglePartitionSpec:
+			PARTITION qualified_name PartitionBoundSpec
+				{
+					SinglePartitionSpec *n = makeNode(SinglePartitionSpec);
+
+					n->name = $2;
+					n->bound = $3;
+
+					$$ = n;
+				}
+		;
+
 partition_cmd:
 			/* ALTER TABLE <name> ATTACH PARTITION <table_name> FOR VALUES */
 			ATTACH PARTITION qualified_name PartitionBoundSpec
@@ -2314,6 +2334,20 @@ partition_cmd:
 					n->def = (Node *) cmd;
 					$$ = (Node *) n;
 				}
+			/* ALTER TABLE <name> SPLIT PARTITION <partition_name> INTO () */
+			| SPLIT PARTITION qualified_name INTO '(' partitions_list ')'
+				{
+					AlterTableCmd *n = makeNode(AlterTableCmd);
+					PartitionCmd *cmd = makeNode(PartitionCmd);
+
+					n->subtype = AT_SplitPartition;
+					cmd->name = $3;
+					cmd->bound = NULL;
+					cmd->partlist = $6;
+					cmd->concurrent = false;
+					n->def = (Node *) cmd;
+					$$ = (Node *) n;
+				}
 			/* ALTER TABLE <name> MERGE PARTITIONS () INTO <partition_name> */
 			| MERGE PARTITIONS '(' qualified_name_list ')' INTO qualified_name
 				{
@@ -16987,6 +17021,7 @@ unreserved_keyword:
 			| SIMPLE
 			| SKIP
 			| SNAPSHOT
+			| SPLIT
 			| SQL_P
 			| STABLE
 			| STANDALONE_P
@@ -17583,6 +17618,7 @@ bare_label_keyword:
 			| SMALLINT
 			| SNAPSHOT
 			| SOME
+			| SPLIT
 			| SQL_P
 			| STABLE
 			| STANDALONE_P
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index e9fbfc0605..7c0f610548 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -137,7 +137,7 @@ static void transformConstraintAttrs(CreateStmtContext *cxt,
 									 List *constraintList);
 static void transformColumnType(CreateStmtContext *cxt, ColumnDef *column);
 static void setSchemaName(char *context_schema, char **stmt_schema_name);
-static void transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd);
+static void transformPartitionCmd(CreateStmtContext *cxt, PartitionBoundSpec *bound);
 static List *transformPartitionRangeBounds(ParseState *pstate, List *blist,
 										   Relation parent);
 static void validateInfiniteBounds(ParseState *pstate, List *blist);
@@ -3265,6 +3265,43 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
+ * transformPartitionCmdForSplit
+ *		Analyze the ALTER TABLLE ... SPLIT PARTITION command
+ *
+ * For each new partition sps->bound is set to the transformed value of bound.
+ * Does checks for bounds of new partitions.
+ */
+static void
+transformPartitionCmdForSplit(CreateStmtContext *cxt, PartitionCmd *partcmd)
+{
+	Relation	parent = cxt->rel;
+	Oid			splitPartOid;
+	ListCell   *listptr;
+
+	if (parent->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("\"%s\" is not a partitioned table", RelationGetRelationName(parent))));
+
+	/* Transform partition bounds for all partitions in the list: */
+	foreach(listptr, partcmd->partlist)
+	{
+		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
+
+		cxt->partbound = NULL;
+		transformPartitionCmd(cxt, sps->bound);
+		/* Assign transformed value of the partition bound. */
+		sps->bound = cxt->partbound;
+	}
+
+	splitPartOid = RangeVarGetRelid(partcmd->name, NoLock, false);
+
+	/* Then we should check partitions with transformed bounds. */
+	check_partitions_for_split(parent, splitPartOid, partcmd->name, partcmd->partlist, cxt->pstate);
+}
+
+
 /*
  * transformPartitionCmdForMerge
  *		Analyze the ALTER TABLLE ... MERGE PARTITIONS command
@@ -3600,7 +3637,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 				{
 					PartitionCmd *partcmd = (PartitionCmd *) cmd->def;
 
-					transformPartitionCmd(&cxt, partcmd);
+					transformPartitionCmd(&cxt, partcmd->bound);
 					/* assign transformed value of the partition bound */
 					partcmd->bound = cxt.partbound;
 				}
@@ -3608,6 +3645,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 				newcmds = lappend(newcmds, cmd);
 				break;
 
+			case AT_SplitPartition:
 			case AT_MergePartitions:
 				{
 					PartitionCmd *partcmd = (PartitionCmd *) cmd->def;
@@ -3616,7 +3654,11 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 						ereport(ERROR,
 								(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
 								 errmsg("list of new partitions should contains at least two items")));
-					transformPartitionCmdForMerge(&cxt, partcmd);
+
+					if (cmd->subtype == AT_SplitPartition)
+						transformPartitionCmdForSplit(&cxt, partcmd);
+					else
+						transformPartitionCmdForMerge(&cxt, partcmd);
 					newcmds = lappend(newcmds, cmd);
 					break;
 				}
@@ -4012,13 +4054,13 @@ setSchemaName(char *context_schema, char **stmt_schema_name)
 
 /*
  * transformPartitionCmd
- *		Analyze the ATTACH/DETACH PARTITION command
+ *		Analyze the ATTACH/DETACH/SPLIT PARTITION command
  *
- * In case of the ATTACH PARTITION command, cxt->partbound is set to the
- * transformed value of cmd->bound.
+ * In case of the ATTACH/SPLIT PARTITION command, cxt->partbound is set to the
+ * transformed value of bound.
  */
 static void
-transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
+transformPartitionCmd(CreateStmtContext *cxt, PartitionBoundSpec *bound)
 {
 	Relation	parentRel = cxt->rel;
 
@@ -4027,9 +4069,9 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 		case RELKIND_PARTITIONED_TABLE:
 			/* transform the partition bound, if any */
 			Assert(RelationGetPartitionKey(parentRel) != NULL);
-			if (cmd->bound != NULL)
+			if (bound != NULL)
 				cxt->partbound = transformPartitionBound(cxt->pstate, parentRel,
-														 cmd->bound);
+														 bound);
 			break;
 		case RELKIND_PARTITIONED_INDEX:
 
@@ -4037,7 +4079,7 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 			 * A partitioned index cannot have a partition bound set.  ALTER
 			 * INDEX prevents that with its grammar, but not ALTER TABLE.
 			 */
-			if (cmd->bound != NULL)
+			if (bound != NULL)
 				ereport(ERROR,
 						(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
 						 errmsg("\"%s\" is not a partitioned table",
diff --git a/src/backend/partitioning/partbounds.c b/src/backend/partitioning/partbounds.c
index 032ebae595..32f2f9378f 100644
--- a/src/backend/partitioning/partbounds.c
+++ b/src/backend/partitioning/partbounds.c
@@ -5041,10 +5041,69 @@ check_two_partitions_bounds_range(Relation parent,
 	}
 }
 
+/*
+ * check_partitions_not_overlap_list
+ *
+ * (function for BY LIST partitioning)
+ *
+ * This is a helper function for check_partitions_for_split().
+ * Checks that the values of the new partitions do not overlap.
+ *
+ * parent:	partitioned table
+ * parts:	array of SinglePartitionSpec structs with info about split partitions
+ * nparts:	size of array "parts"
+ */
+static void
+check_partitions_not_overlap_list(Relation parent,
+								  SinglePartitionSpec * *parts,
+								  int nparts,
+								  ParseState *pstate)
+{
+	PartitionKey key PG_USED_FOR_ASSERTS_ONLY = RelationGetPartitionKey(parent);
+	int			overlap_location = -1;
+	int			i,
+				j;
+	SinglePartitionSpec *sps1,
+			   *sps2;
+	List	   *overlap;
+
+	Assert(key->strategy == PARTITION_STRATEGY_LIST);
+
+	for (i = 0; i < nparts; i++)
+	{
+		sps1 = parts[i];
+
+		for (j = i + 1; j < nparts; j++)
+		{
+			sps2 = parts[j];
+
+			/*
+			 * Calculate intersection between values of two partitions.
+			 */
+			overlap = list_intersection(sps1->bound->listdatums,
+										sps2->bound->listdatums);
+			if (list_length(overlap) > 0)
+			{
+				Const	   *val = (Const *) lfirst(list_head(overlap));
+
+				overlap_location = val->location;
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+						 errmsg("new partition \"%s\" would overlap with another new partition \"%s\"",
+								sps1->name->relname, sps2->name->relname),
+						 parser_errposition(pstate, overlap_location)));
+			}
+		}
+	}
+}
+
 /*
  * get_partition_bound_spec
  *
  * Returns description of partition with Oid "partOid" and name "name".
+ *
+ * partOid:	partition Oid
+ * name:	partition name
  */
 static PartitionBoundSpec *
 get_partition_bound_spec(Oid partOid, RangeVar *name)
@@ -5077,6 +5136,602 @@ get_partition_bound_spec(Oid partOid, RangeVar *name)
 	return boundspec;
 }
 
+/*
+ * check_partition_bounds_for_split_range
+ *
+ * (function for BY RANGE partitioning)
+ *
+ * Checks that bounds of new partition "spec" is inside bounds of split
+ * partition (with Oid splitPartOid). If first=true (this means that "spec" is
+ * the first of new partitions) then lower bound of "spec" should be equal (or
+ * greater than or equal in case defaultPart=true) to lower bound of split
+ * partition. If last=true (this means that "spec" is the last of new
+ * partitions) then upper bound of of "spec" should be equal (or less than or
+ * equal in case defaultPart=true) to upper bound of split partition.
+ *
+ * parent:			partitioned table
+ * relname:			name of the new partition
+ * spec:			bounds specification of the new partition
+ * splitPartOid:	split partition Oid
+ * splitPartName:	split partition name
+ * first:			true in case new partition "spec" is first of new partitions
+ * last:			true in case new partition "spec" is last of new partitions
+ * defaultPart:		true in case partitioned table has DEFAULT partition
+ * pstate:			pointer to ParseState struct for determine error position
+ */
+static void
+check_partition_bounds_for_split_range(Relation parent,
+									   char *relname,
+									   PartitionBoundSpec *spec,
+									   Oid splitPartOid,
+									   RangeVar *splitPartName,
+									   bool first,
+									   bool last,
+									   bool defaultPart,
+									   ParseState *pstate)
+{
+	PartitionKey key = RelationGetPartitionKey(parent);
+	PartitionRangeBound *lower,
+			   *upper;
+	int			cmpval;
+
+	Assert(key->strategy == PARTITION_STRATEGY_RANGE);
+	Assert(spec->strategy == PARTITION_STRATEGY_RANGE);
+
+	lower = make_one_partition_rbound(key, -1, spec->lowerdatums, true);
+	upper = make_one_partition_rbound(key, -1, spec->upperdatums, false);
+
+	/*
+	 * First check if the resulting range would be empty with specified lower
+	 * and upper bounds.  partition_rbound_cmp cannot return zero here, since
+	 * the lower-bound flags are different.
+	 */
+	cmpval = partition_rbound_cmp(key->partnatts,
+								  key->partsupfunc,
+								  key->partcollation,
+								  lower->datums, lower->kind,
+								  true, upper);
+	Assert(cmpval != 0);
+	if (cmpval > 0)
+	{
+		/* Point to problematic key in the lower datums list. */
+		PartitionRangeDatum *datum = list_nth(spec->lowerdatums, cmpval - 1);
+
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("empty range bound specified for partition \"%s\"",
+						relname),
+				 errdetail("Specified lower bound %s is greater than or equal to upper bound %s.",
+						   get_range_partbound_string(spec->lowerdatums),
+						   get_range_partbound_string(spec->upperdatums)),
+				 parser_errposition(pstate, datum->location)));
+	}
+
+	/* Need to check first and last partitions (from set of new partitions) */
+	if (first || last)
+	{
+		PartitionBoundSpec *split_spec = get_partition_bound_spec(splitPartOid, splitPartName);
+		bool		overlap = false;
+
+		if (first)
+		{
+			PartitionRangeBound *split_lower;
+
+			split_lower = make_one_partition_rbound(key, -1, split_spec->lowerdatums, true);
+
+			cmpval = partition_rbound_cmp(key->partnatts,
+										  key->partsupfunc,
+										  key->partcollation,
+										  lower->datums, lower->kind,
+										  true, split_lower);
+
+			/*
+			 * Lower bound of "spec" should be equal (or greater than or equal
+			 * in case defaultPart=true) to lower bound of split partition.
+			 */
+			if ((!defaultPart && cmpval) || (defaultPart && cmpval < 0))
+				overlap = true;
+		}
+		else
+		{
+			PartitionRangeBound *split_upper;
+
+			split_upper = make_one_partition_rbound(key, -1, split_spec->upperdatums, false);
+
+			cmpval = partition_rbound_cmp(key->partnatts,
+										  key->partsupfunc,
+										  key->partcollation,
+										  upper->datums, upper->kind,
+										  false, split_upper);
+
+			/*
+			 * Upper bound of of "spec" should be equal (or less than or equal
+			 * in case defaultPart=true) to upper bound of split partition.
+			 */
+			if ((!defaultPart && cmpval) || (defaultPart && cmpval > 0))
+				overlap = true;
+		}
+
+		if (overlap)
+		{
+			PartitionRangeDatum *datum;
+
+			datum = list_nth(first ? spec->lowerdatums : spec->upperdatums, abs(cmpval) - 1);
+
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+					 errmsg("%s bound of partition \"%s\" is %s %s bound of split partition",
+							first ? "lower" : "upper",
+							relname,
+							defaultPart ? (first ? "less than" : "greater than") : "not equals to",
+							first ? "lower" : "upper"),
+					 parser_errposition(pstate, datum->location)));
+		}
+	}
+}
+
+/*
+ * check_partition_bounds_for_split_list
+ *
+ * (function for BY LIST partitioning)
+ *
+ * Checks that bounds of new partition is inside bounds of split partition
+ * (with Oid splitPartOid).
+ *
+ * parent:			partitioned table
+ * relname:			name of the new partition
+ * spec:			bounds specification of the new partition
+ * splitPartOid:	split partition Oid
+ * pstate:			pointer to ParseState struct for determine error position
+ */
+static void
+check_partition_bounds_for_split_list(Relation parent, char *relname,
+									  PartitionBoundSpec *spec,
+									  Oid splitPartOid,
+									  ParseState *pstate)
+{
+	PartitionKey key = RelationGetPartitionKey(parent);
+	PartitionDesc partdesc = RelationGetPartitionDesc(parent, false);
+	PartitionBoundInfo boundinfo = partdesc->boundinfo;
+	int			with = -1;
+	bool		overlap = false;
+	int			overlap_location = -1;
+	ListCell   *cell;
+
+	Assert(key->strategy == PARTITION_STRATEGY_LIST);
+	Assert(spec->strategy == PARTITION_STRATEGY_LIST);
+	Assert(boundinfo && boundinfo->strategy == PARTITION_STRATEGY_LIST);
+
+	/*
+	 * Search each value of new partition "spec" in existing partitions. All
+	 * of them should be in split partition (with Oid splitPartOid).
+	 */
+	foreach(cell, spec->listdatums)
+	{
+		Const	   *val = lfirst_node(Const, cell);
+
+		overlap_location = val->location;
+		if (!val->constisnull)
+		{
+			int			offset;
+			bool		equal;
+
+			offset = partition_list_bsearch(&key->partsupfunc[0],
+											key->partcollation,
+											boundinfo,
+											val->constvalue,
+											&equal);
+			if (offset >= 0 && equal)
+			{
+				with = boundinfo->indexes[offset];
+				if (partdesc->oids[with] != splitPartOid)
+				{
+					overlap = true;
+					break;
+				}
+			}
+			else
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+						 errmsg("new partition \"%s\" cannot have this value because split partition does not have",
+								relname),
+						 parser_errposition(pstate, overlap_location)));
+		}
+		else if (partition_bound_accepts_nulls(boundinfo))
+		{
+			with = boundinfo->null_index;
+			if (partdesc->oids[with] != splitPartOid)
+			{
+				overlap = true;
+				break;
+			}
+		}
+		else
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+					 errmsg("new partition \"%s\" cannot have NULL value because split partition does not have",
+							relname),
+					 parser_errposition(pstate, overlap_location)));
+	}
+
+	if (overlap)
+	{
+		Assert(with >= 0);
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("new partition \"%s\" would overlap with another (not split) partition \"%s\"",
+						relname, get_rel_name(partdesc->oids[with])),
+				 parser_errposition(pstate, overlap_location)));
+	}
+}
+
+/*
+ * find_value_in_new_partitions
+ *
+ * (function for BY LIST partitioning)
+ *
+ * Function returns true in case any of new partitions contains value "value".
+ *
+ * partsupfunc:		information about comparison function associated with the partition key
+ * partcollation:	partitioning collation
+ * parts:			pointer to array with new partitions descriptions
+ * nparts:			number of new partitions
+ * value:			the value that we are looking for
+ * isnull:			true if the value that we are looking for is NULL
+ */
+static bool
+find_value_in_new_partitions_list(FmgrInfo *partsupfunc,
+								  Oid *partcollation,
+								  SinglePartitionSpec * *parts,
+								  int nparts,
+								  Datum value,
+								  bool isnull)
+{
+	ListCell   *valptr;
+	int			i;
+
+	for (i = 0; i < nparts; i++)
+	{
+		SinglePartitionSpec *sps = parts[i];
+
+		foreach(valptr, sps->bound->listdatums)
+		{
+			Const	   *val = lfirst_node(Const, valptr);
+
+			if (isnull && val->constisnull)
+				return true;
+
+			if (!isnull && !val->constisnull)
+			{
+				if (DatumGetInt32(FunctionCall2Coll(&partsupfunc[0],
+													partcollation[0],
+													val->constvalue,
+													value)) == 0)
+					return true;
+			}
+		}
+	}
+	return false;
+}
+
+/*
+ * check_parent_values_in_new_partitions
+ *
+ * (function for BY LIST partitioning)
+ *
+ * Checks that all values of split partition (with Oid partOid) contains in new
+ * partitions.
+ *
+ * parent:	partitioned table
+ * partOid:	split partition Oid
+ * parts:	pointer to array with new partitions descriptions
+ * nparts:	number of new partitions
+ * pstate:	pointer to ParseState struct for determine error position
+ */
+static void
+check_parent_values_in_new_partitions(Relation parent,
+									  Oid partOid,
+									  SinglePartitionSpec * *parts,
+									  int nparts,
+									  ParseState *pstate)
+{
+	PartitionKey key = RelationGetPartitionKey(parent);
+	PartitionDesc partdesc = RelationGetPartitionDesc(parent, false);
+	PartitionBoundInfo boundinfo = partdesc->boundinfo;
+	int			i;
+	bool		found = true;
+	bool		searchNull = false;
+	Datum		datum = PointerGetDatum(NULL);
+
+	Assert(key->strategy == PARTITION_STRATEGY_LIST);
+
+	/*
+	 * Special processing for NULL value. Search NULL-value if it contains
+	 * split partition (partOid).
+	 */
+	if (partition_bound_accepts_nulls(boundinfo) &&
+		partdesc->oids[boundinfo->null_index] == partOid)
+	{
+		if (!find_value_in_new_partitions_list(&key->partsupfunc[0],
+											   key->partcollation, parts, nparts, datum, true))
+		{
+			found = false;
+			searchNull = true;
+		}
+	}
+
+	/*
+	 * Search all values of split partition with partOid in PartitionDesc of
+	 * partitionde table.
+	 */
+	for (i = 0; i < boundinfo->ndatums; i++)
+	{
+		if (partdesc->oids[boundinfo->indexes[i]] == partOid)
+		{
+			/* We found value that split partition contains. */
+			datum = boundinfo->datums[i][0];
+			if (!find_value_in_new_partitions_list(&key->partsupfunc[0],
+												   key->partcollation, parts, nparts, datum, false))
+			{
+				found = false;
+				break;
+			}
+		}
+	}
+
+	if (!found)
+	{
+		Const	   *notFoundVal;
+
+		if (!searchNull)
+			/* Make Const for get string representation of not found value. */
+			notFoundVal = makeConst(key->parttypid[0],
+									key->parttypmod[0],
+									key->parttypcoll[0],
+									key->parttyplen[0],
+									datum,
+									false,	/* isnull */
+									key->parttypbyval[0]);
+
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("new partitions not have value %s but split partition has",
+						searchNull ? "NULL" : get_list_partvalue_string(notFoundVal))));
+	}
+}
+
+/*
+ * check_partitions_for_split
+ *
+ * Checks new partitions for SPLIT PARTITIONS command:
+ * 1. DEFAULT partition should be one.
+ * 2. New partitions should have different names
+ *    (with existing partitions too).
+ * 3. Bounds of new partitions should not overlap with new and existing
+ *    partitions.
+ * 4. In case split partition is DEFAULT partition, one of new partitions
+ *    should be DEFAULT.
+ * 5. In case new partitions or existing partitions contains DEFAULT
+ *    partition, new partitions can have any bounds inside split
+ *    partition bound (can be spaces between partitions bounds).
+ * 6. In case partitioned table does not have DEFAULT partition, DEFAULT
+ *    partition can be defined as one of new partition.
+ * 7. In case new partitions not contains DEFAULT partition and
+ *    partitioned table does not have DEFAULT partition the following
+ *    should be true: sum bounds of new partitions should be equal
+ *    to bound of split partition.
+ *
+ * parent:			partitioned table
+ * splitPartOid:	split partition Oid
+ * splitPartName:	split partition name
+ * list:			list of new partitions
+ * pstate:			pointer to ParseState struct for determine error position
+ */
+void
+check_partitions_for_split(Relation parent,
+						   Oid splitPartOid,
+						   RangeVar *splitPartName,
+						   List *partlist,
+						   ParseState *pstate)
+{
+	PartitionKey key;
+	char		strategy;
+	Oid			defaultPartOid;
+	bool		isSplitPartDefault;
+	bool		existsDefaultPart;
+	ListCell   *listptr;
+	int			default_index = -1;
+	int			i,
+				j;
+	SinglePartitionSpec **new_parts;
+	SinglePartitionSpec *spsPrev = NULL;
+	int			nparts = 0;
+
+	key = RelationGetPartitionKey(parent);
+	strategy = get_partition_strategy(key);
+
+	switch (strategy)
+	{
+		case PARTITION_STRATEGY_LIST:
+		case PARTITION_STRATEGY_RANGE:
+			{
+				/*
+				 * Make array new_parts with new partitions except DEFAULT
+				 * partition.
+				 */
+				new_parts = (SinglePartitionSpec * *)
+					palloc0(list_length(partlist) * sizeof(SinglePartitionSpec *));
+				i = -1;
+				foreach(listptr, partlist)
+				{
+					SinglePartitionSpec *sps =
+					(SinglePartitionSpec *) lfirst(listptr);
+
+					i++;
+					if (sps->bound->is_default)
+					{
+						if (default_index >= 0)
+							ereport(ERROR,
+									(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+									 errmsg("DEFAULT partition should be one")),
+									parser_errposition(pstate, sps->name->location));
+						default_index = i;
+						continue;
+					}
+					new_parts[nparts++] = sps;
+				}
+			}
+			break;
+
+		case PARTITION_STRATEGY_HASH:
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("partition of hash-partitioned table cannot be split")));
+			break;
+
+		default:
+			elog(ERROR, "unexpected partition strategy: %d",
+				 (int) key->strategy);
+			break;
+	}
+
+	if (strategy == PARTITION_STRATEGY_RANGE)
+	{
+		PartitionRangeBound **lower_bounds;
+		SinglePartitionSpec **tmp_new_parts;
+
+		/*
+		 * For simplify check for ranges of new partitions need to sort all
+		 * partitions in ascending order of them bounds (we compare upper
+		 * bound only).
+		 */
+		lower_bounds = (PartitionRangeBound **)
+			palloc0(nparts * sizeof(PartitionRangeBound *));
+
+		/* Create array of lower bounds. */
+		for (i = 0; i < nparts; i++)
+		{
+			lower_bounds[i] = make_one_partition_rbound(key, i,
+														new_parts[i]->bound->lowerdatums, true);
+		}
+
+		/* Sort array of lower bounds. */
+		qsort_arg(lower_bounds, nparts, sizeof(PartitionRangeBound *),
+				  qsort_partition_rbound_cmp, (void *) key);
+
+		/* Reorder array of partitions. */
+		tmp_new_parts = new_parts;
+		new_parts = (SinglePartitionSpec * *)
+			palloc0(nparts * sizeof(SinglePartitionSpec *));
+		for (i = 0; i < nparts; i++)
+			new_parts[i] = tmp_new_parts[lower_bounds[i]->index];
+
+		pfree(tmp_new_parts);
+		pfree(lower_bounds);
+	}
+
+	defaultPartOid =
+		get_default_oid_from_partdesc(RelationGetPartitionDesc(parent, true));
+
+	/* isSplitPartDefault flag: is split partition a DEFAULT partition? */
+	isSplitPartDefault = (defaultPartOid == splitPartOid);
+
+	if (isSplitPartDefault && default_index < 0)
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("any partition in the list should be DEFAULT because split partition is DEFAULT")),
+				parser_errposition(pstate, ((SinglePartitionSpec *) linitial(partlist))->name->location));
+	}
+	else if (!isSplitPartDefault && (default_index >= 0) && OidIsValid(defaultPartOid))
+	{
+		SinglePartitionSpec *spsDef =
+		(SinglePartitionSpec *) list_nth(partlist, default_index);
+
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+				 errmsg("new partition cannot be DEFAULT because DEFAULT partition already exists")),
+				parser_errposition(pstate, spsDef->name->location));
+	}
+
+	/* Indicator that partitioned table has (or will have) DEFAULT partition */
+	existsDefaultPart = OidIsValid(defaultPartOid) || (default_index >= 0);
+
+	for (i = 0; i < nparts; i++)
+	{
+		SinglePartitionSpec *sps = new_parts[i];
+
+		if (isSplitPartDefault)
+		{
+			/*
+			 * In case split partition is DEFAULT partition we can use any
+			 * free ranges - as when creating a new partition.
+			 */
+			check_new_partition_bound(sps->name->relname, parent, sps->bound,
+									  pstate);
+		}
+		else
+		{
+			/*
+			 * Checks that bound of current partition is inside bound of split
+			 * partition. For range partitioning: checks that upper bound of
+			 * previous partition is equal to lower bound of current
+			 * partition. For list partitioning: checks that split partition
+			 * contains all values of current partition.
+			 */
+			if (strategy == PARTITION_STRATEGY_RANGE)
+			{
+				bool		first = (i == 0);
+				bool		last = (i == (nparts - 1));
+
+				check_partition_bounds_for_split_range(parent, sps->name->relname, sps->bound,
+													   splitPartOid, splitPartName,
+													   first, last,
+													   existsDefaultPart, pstate);
+			}
+			else
+				check_partition_bounds_for_split_list(parent, sps->name->relname,
+													  sps->bound, splitPartOid, pstate);
+		}
+
+		/* Ranges of new partitions should not overlap. */
+		if (strategy == PARTITION_STRATEGY_RANGE && spsPrev)
+			check_two_partitions_bounds_range(parent, spsPrev->name, spsPrev->bound,
+											  sps->name, sps->bound, existsDefaultPart, pstate);
+
+		spsPrev = sps;
+
+		/* Check: new partitions should have different names. */
+		for (j = i + 1; j < nparts; j++)
+		{
+			SinglePartitionSpec *sps2 = new_parts[j];
+
+			if (equal(sps->name, sps2->name))
+				ereport(ERROR,
+						(errcode(ERRCODE_DUPLICATE_TABLE),
+						 errmsg("name \"%s\" already used", sps2->name->relname)),
+						parser_errposition(pstate, sps2->name->location));
+		}
+	}
+
+	if (strategy == PARTITION_STRATEGY_LIST)
+	{
+		/* Values of new partitions should not overlap. */
+		check_partitions_not_overlap_list(parent, new_parts, nparts,
+										  pstate);
+
+		/*
+		 * Need to check that all values of split partition contains in new
+		 * partitions. Skip this check if DEFAULT partition exists.
+		 */
+		if (!existsDefaultPart)
+			check_parent_values_in_new_partitions(parent, splitPartOid,
+												  new_parts, nparts, pstate);
+	}
+
+	pfree(new_parts);
+}
+
 /*
  * calculate_partition_bound_for_merge
  *
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 4a98b82f07..387de61b51 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -12182,3 +12182,21 @@ get_range_partbound_string(List *bound_datums)
 
 	return buf->data;
 }
+
+/*
+ * get_list_partvalue_string
+ *		A C string representation of one list partition value
+ */
+char *
+get_list_partvalue_string(Const *val)
+{
+	deparse_context context;
+	StringInfo	buf = makeStringInfo();
+
+	memset(&context, 0, sizeof(deparse_context));
+	context.buf = buf;
+
+	get_const_expr(val, &context, -1);
+
+	return buf->data;
+}
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index f5c0625bbf..f8031c609e 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2138,6 +2138,7 @@ typedef enum AlterTableType
 	AT_AttachPartition,			/* ATTACH PARTITION */
 	AT_DetachPartition,			/* DETACH PARTITION */
 	AT_DetachPartitionFinalize, /* DETACH PARTITION FINALIZE */
+	AT_SplitPartition,			/* SPLIT PARTITION */
 	AT_MergePartitions,			/* MERGE PARTITIONS */
 	AT_AddIdentity,				/* ADD IDENTITY */
 	AT_SetIdentity,				/* SET identity column options */
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h
index 2abe9d7d7d..f855a33261 100644
--- a/src/include/parser/kwlist.h
+++ b/src/include/parser/kwlist.h
@@ -393,6 +393,7 @@ PG_KEYWORD("skip", SKIP, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("smallint", SMALLINT, COL_NAME_KEYWORD, BARE_LABEL)
 PG_KEYWORD("snapshot", SNAPSHOT, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("some", SOME, RESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("split", SPLIT, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("sql", SQL_P, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("stable", STABLE, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("standalone", STANDALONE_P, UNRESERVED_KEYWORD, BARE_LABEL)
diff --git a/src/include/partitioning/partbounds.h b/src/include/partitioning/partbounds.h
index 2fe80fb4fc..97e9185579 100644
--- a/src/include/partitioning/partbounds.h
+++ b/src/include/partitioning/partbounds.h
@@ -143,6 +143,11 @@ extern int	partition_range_datum_bsearch(FmgrInfo *partsupfunc,
 extern int	partition_hash_bsearch(PartitionBoundInfo boundinfo,
 								   int modulus, int remainder);
 
+extern void check_partitions_for_split(Relation parent,
+									   Oid splitPartOid,
+									   RangeVar *splitPartName,
+									   List *partlist,
+									   ParseState *pstate);
 extern void calculate_partition_bound_for_merge(Relation parent,
 												List *partNames,
 												List *partOids,
diff --git a/src/include/utils/ruleutils.h b/src/include/utils/ruleutils.h
index 1a42d9f39b..e9b431dd4f 100644
--- a/src/include/utils/ruleutils.h
+++ b/src/include/utils/ruleutils.h
@@ -44,4 +44,6 @@ extern char *get_range_partbound_string(List *bound_datums);
 
 extern char *pg_get_statisticsobjdef_string(Oid statextid);
 
+extern char *get_list_partvalue_string(Const *val);
+
 #endif							/* RULEUTILS_H */
diff --git a/src/test/isolation/expected/partition-split.out b/src/test/isolation/expected/partition-split.out
new file mode 100644
index 0000000000..5d9e8b0925
--- /dev/null
+++ b/src/test/isolation/expected/partition-split.out
@@ -0,0 +1,190 @@
+Parsed test spec with 2 sessions
+
+starting permutation: s1b s1splt s2b s2i s1c s2c s2s
+step s1b: BEGIN;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2b: BEGIN;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1b s1splt s2brr s2i s1c s2c s2s
+step s1b: BEGIN;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1b s1splt s2bs s2i s1c s2c s2s
+step s1b: BEGIN;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1brr s1splt s2b s2i s1c s2c s2s
+step s1brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2b: BEGIN;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1brr s1splt s2brr s2i s1c s2c s2s
+step s1brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1brr s1splt s2bs s2i s1c s2c s2s
+step s1brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1bs s1splt s2b s2i s1c s2c s2s
+step s1bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2b: BEGIN;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1bs s1splt s2brr s2i s1c s2c s2s
+step s1bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2brr: BEGIN ISOLATION LEVEL REPEATABLE READ;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
+
+starting permutation: s1bs s1splt s2bs s2i s1c s2c s2s
+step s1bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s1splt: ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20));
+step s2bs: BEGIN ISOLATION LEVEL SERIALIZABLE;
+step s2i: INSERT INTO tpart VALUES (1, 'text01'); <waiting ...>
+step s1c: COMMIT;
+step s2i: <... completed>
+step s2c: COMMIT;
+step s2s: SELECT * FROM tpart;
+ i|t     
+--+------
+ 5|text05
+ 1|text01
+15|text15
+25|text25
+35|text35
+(5 rows)
+
diff --git a/src/test/isolation/isolation_schedule b/src/test/isolation/isolation_schedule
index 2a98bccbf6..60e2475ac6 100644
--- a/src/test/isolation/isolation_schedule
+++ b/src/test/isolation/isolation_schedule
@@ -103,6 +103,7 @@ test: partition-key-update-2
 test: partition-key-update-3
 test: partition-key-update-4
 test: partition-merge
+test: partition-split
 test: plpgsql-toast
 test: cluster-conflict
 test: cluster-conflict-partition
diff --git a/src/test/isolation/specs/partition-split.spec b/src/test/isolation/specs/partition-split.spec
new file mode 100644
index 0000000000..087239a4a1
--- /dev/null
+++ b/src/test/isolation/specs/partition-split.spec
@@ -0,0 +1,54 @@
+# Verify that SPLIT operation locks DML operations with partitioned table
+
+setup
+{
+  DROP TABLE IF EXISTS tpart;
+  CREATE TABLE tpart(i int, t text) partition by range(i);
+  CREATE TABLE tpart_00_10 PARTITION OF tpart FOR VALUES FROM (0) TO (10);
+  CREATE TABLE tpart_10_20 PARTITION OF tpart FOR VALUES FROM (10) TO (20);
+  CREATE TABLE tpart_20_30 PARTITION OF tpart FOR VALUES FROM (20) TO (30);
+  CREATE TABLE tpart_default PARTITION OF tpart DEFAULT;
+  INSERT INTO tpart VALUES (5, 'text05');
+  INSERT INTO tpart VALUES (15, 'text15');
+  INSERT INTO tpart VALUES (25, 'text25');
+  INSERT INTO tpart VALUES (35, 'text35');
+}
+
+teardown
+{
+  DROP TABLE tpart;
+}
+
+session s1
+step s1b	{ BEGIN; }
+step s1brr	{ BEGIN ISOLATION LEVEL REPEATABLE READ; }
+step s1bs	{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
+step s1splt	{ ALTER TABLE tpart SPLIT PARTITION tpart_10_20 INTO
+			   (PARTITION tpart_10_15 FOR VALUES FROM (10) TO (15),
+			    PARTITION tpart_15_20 FOR VALUES FROM (15) TO (20)); }
+step s1c	{ COMMIT; }
+
+
+session s2
+step s2b	{ BEGIN; }
+step s2brr	{ BEGIN ISOLATION LEVEL REPEATABLE READ; }
+step s2bs	{ BEGIN ISOLATION LEVEL SERIALIZABLE; }
+step s2i	{ INSERT INTO tpart VALUES (1, 'text01'); }
+step s2c	{ COMMIT; }
+step s2s	{ SELECT * FROM tpart; }
+
+
+# s1 starts SPLIT PARTITION then s2 trying to insert row and
+# waits until s1 finished SPLIT operation.
+
+permutation s1b s1splt s2b s2i s1c s2c s2s
+permutation s1b s1splt s2brr s2i s1c s2c s2s
+permutation s1b s1splt s2bs s2i s1c s2c s2s
+
+permutation s1brr s1splt s2b s2i s1c s2c s2s
+permutation s1brr s1splt s2brr s2i s1c s2c s2s
+permutation s1brr s1splt s2bs s2i s1c s2c s2s
+
+permutation s1bs s1splt s2b s2i s1c s2c s2s
+permutation s1bs s1splt s2brr s2i s1c s2c s2s
+permutation s1bs s1splt s2bs s2i s1c s2c s2s
diff --git a/src/test/modules/test_ddl_deparse/test_ddl_deparse.c b/src/test/modules/test_ddl_deparse/test_ddl_deparse.c
index b4171dd382..6b296f81ec 100644
--- a/src/test/modules/test_ddl_deparse/test_ddl_deparse.c
+++ b/src/test/modules/test_ddl_deparse/test_ddl_deparse.c
@@ -297,6 +297,9 @@ get_altertable_subcmdinfo(PG_FUNCTION_ARGS)
 			case AT_DetachPartitionFinalize:
 				strtype = "DETACH PARTITION ... FINALIZE";
 				break;
+			case AT_SplitPartition:
+				strtype = "SPLIT PARTITION";
+				break;
 			case AT_MergePartitions:
 				strtype = "MERGE PARTITIONS";
 				break;
diff --git a/src/test/regress/expected/partition_split.out b/src/test/regress/expected/partition_split.out
new file mode 100644
index 0000000000..08bf021796
--- /dev/null
+++ b/src/test/regress/expected/partition_split.out
@@ -0,0 +1,1417 @@
+--
+-- PARTITION_SPLIT
+-- Tests for "ALTER TABLE ... SPLIT PARTITION ..." command
+--
+CREATE SCHEMA partition_split_schema;
+SET search_path = partition_split_schema, public;
+--
+-- BY RANGE partitioning
+--
+--
+-- Test for error codes
+--
+CREATE TABLE sales_range (salesman_id int, salesman_name varchar(30), sales_amount int, sales_date date) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+-- ERROR:  relation "sales_xxx" does not exist
+ALTER TABLE sales_range SPLIT PARTITION sales_xxx INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  relation "sales_xxx" does not exist
+-- ERROR:  relation "sales_jan2022" already exists
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  relation "sales_jan2022" already exists
+-- ERROR:  invalid bound specification for a range partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES IN ('2022-05-01', '2022-06-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  invalid bound specification for a range partition
+LINE 2:   (PARTITION sales_jan2022 FOR VALUES IN ('2022-05-01', '202...
+                                              ^
+-- ERROR:  empty range bound specified for partition "sales_mar2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-02-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  empty range bound specified for partition "sales_mar2022"
+LINE 3:    PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO...
+                                                    ^
+DETAIL:  Specified lower bound ('03-01-2022') is greater than or equal to upper bound ('02-01-2022').
+--ERROR:  list of split partitions should contains at least two items
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-10-01'));
+ERROR:  list of new partitions should contains at least two items
+-- ERROR:  lower bound of partition "sales_feb2022" is less than lower bound of split partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-01-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  lower bound of partition "sales_feb2022" is less than lower bound of split partition
+LINE 2:   (PARTITION sales_feb2022 FOR VALUES FROM ('2022-01-01') TO...
+                                                    ^
+-- ERROR:  name "sales_feb_mar_apr2022" already used
+-- (We can create partition with the same name as split partition, but can't create two partitions with the same name)
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb_mar_apr2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_feb_mar_apr2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  name "sales_feb_mar_apr2022" already used
+LINE 3:    PARTITION sales_feb_mar_apr2022 FOR VALUES FROM ('2022-03...
+                     ^
+-- ERROR:  name "sales_feb2022" already used
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_feb2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  name "sales_feb2022" already used
+LINE 3:    PARTITION sales_feb2022 FOR VALUES FROM ('2022-03-01') TO...
+                     ^
+-- ERROR:  "sales_feb_mar_apr2022" is not a partitioned table
+ALTER TABLE sales_feb_mar_apr2022 SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_feb2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  "sales_feb_mar_apr2022" is not a partitioned table
+-- ERROR:  upper bound of partition "sales_apr2022" is greater than upper bound of split partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-06-01'));
+ERROR:  upper bound of partition "sales_apr2022" is greater than upper bound of split partition
+LINE 4: ... sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-06-0...
+                                                             ^
+-- ERROR:  lower bound of partition "sales_mar2022" is not equals to upper bound of previous partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-02-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  lower bound of partition "sales_mar2022" conflicts with upper bound of previous partition "sales_feb2022"
+LINE 3:    PARTITION sales_mar2022 FOR VALUES FROM ('2022-02-01') TO...
+                                                    ^
+-- Tests for spaces between partitions, them should be executed without DEFAULT partition
+ALTER TABLE sales_range DETACH PARTITION sales_others;
+-- ERROR:  lower bound of partition "sales_feb2022" is not equals to lower bound of split partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-02') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+ERROR:  lower bound of partition "sales_feb2022" is not equals to lower bound of split partition
+LINE 2:   (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-02') TO...
+                                                    ^
+DROP TABLE sales_range;
+DROP TABLE sales_others;
+--
+-- Add rows into partitioned table then split partition
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_jan2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+(3 rows)
+
+SELECT * FROM sales_feb2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+(3 rows)
+
+SELECT * FROM sales_mar2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+(3 rows)
+
+SELECT * FROM sales_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(4 rows)
+
+SELECT * FROM sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          14 | Smith         |          510 | 05-04-2022
+(1 row)
+
+DROP TABLE sales_range CASCADE;
+--
+-- Add split partition then add rows into partitioned table
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_jan2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+(3 rows)
+
+SELECT * FROM sales_feb2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+(3 rows)
+
+SELECT * FROM sales_mar2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+(3 rows)
+
+SELECT * FROM sales_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(4 rows)
+
+SELECT * FROM sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          14 | Smith         |          510 | 05-04-2022
+(1 row)
+
+DROP TABLE sales_range CASCADE;
+--
+-- Test for:
+--   * composite partition key;
+--   * GENERATED column;
+--   * column with DEFAULT value.
+--
+CREATE TABLE sales_date (salesman_name VARCHAR(30), sales_year INT, sales_month INT, sales_day INT,
+  sales_date VARCHAR(10) GENERATED ALWAYS AS
+    (LPAD(sales_year::text, 4, '0') || '.' || LPAD(sales_month::text, 2, '0') || '.' || LPAD(sales_day::text, 2, '0')) STORED,
+  sales_department VARCHAR(30) DEFAULT 'Sales department')
+  PARTITION BY RANGE (sales_year, sales_month, sales_day);
+CREATE TABLE sales_dec2022 PARTITION OF sales_date FOR VALUES FROM (2021, 12, 1) TO (2022, 1, 1);
+CREATE TABLE sales_jan_feb2022 PARTITION OF sales_date FOR VALUES FROM (2022, 1, 1) TO (2022, 3, 1);
+CREATE TABLE sales_other PARTITION OF sales_date FOR VALUES FROM (2022, 3, 1) TO (MAXVALUE, MAXVALUE, MAXVALUE);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2021, 12, 7);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2021, 12, 8);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 1, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 2, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 1, 2);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 2, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 3, 3);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 3, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 5, 1);
+SELECT * FROM sales_date;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(9 rows)
+
+SELECT * FROM sales_dec2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+(2 rows)
+
+SELECT * FROM sales_jan_feb2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+(4 rows)
+
+SELECT * FROM sales_other;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(3 rows)
+
+ALTER TABLE sales_date SPLIT PARTITION sales_jan_feb2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES FROM (2022, 1, 1) TO (2022, 2, 1),
+   PARTITION sales_feb2022 FOR VALUES FROM (2022, 2, 1) TO (2022, 3, 1));
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 1, 10);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 2, 10);
+SELECT * FROM sales_date;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+ Manager1      |       2022 |           1 |        10 | 2022.01.10 | Sales department
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+ Manager2      |       2022 |           2 |        10 | 2022.02.10 | Sales department
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(11 rows)
+
+SELECT * FROM sales_dec2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2021 |          12 |         7 | 2021.12.07 | Sales department
+ Manager2      |       2021 |          12 |         8 | 2021.12.08 | Sales department
+(2 rows)
+
+SELECT * FROM sales_jan2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager3      |       2022 |           1 |         1 | 2022.01.01 | Sales department
+ Manager2      |       2022 |           1 |         2 | 2022.01.02 | Sales department
+ Manager1      |       2022 |           1 |        10 | 2022.01.10 | Sales department
+(3 rows)
+
+SELECT * FROM sales_feb2022;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2022 |           2 |         4 | 2022.02.04 | Sales department
+ Manager3      |       2022 |           2 |         1 | 2022.02.01 | Sales department
+ Manager2      |       2022 |           2 |        10 | 2022.02.10 | Sales department
+(3 rows)
+
+SELECT * FROM sales_other;
+ salesman_name | sales_year | sales_month | sales_day | sales_date | sales_department 
+---------------+------------+-------------+-----------+------------+------------------
+ Manager1      |       2022 |           3 |         3 | 2022.03.03 | Sales department
+ Manager2      |       2022 |           3 |         4 | 2022.03.04 | Sales department
+ Manager3      |       2022 |           5 |         1 | 2022.05.01 | Sales department
+(3 rows)
+
+--ERROR:  relation "sales_jan_feb2022" does not exist
+SELECT * FROM sales_jan_feb2022;
+ERROR:  relation "sales_jan_feb2022" does not exist
+LINE 1: SELECT * FROM sales_jan_feb2022;
+                      ^
+DROP TABLE sales_date CASCADE;
+--
+-- Test: split DEFAULT partition; using a index on partition key; check index after split
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+SELECT * FROM sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-10-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+           6 | Poirot        |          150 | 02-11-2022
+           7 | Li            |          175 | 03-08-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           9 | Muller        |          250 | 03-11-2022
+          11 | Trump         |          380 | 04-06-2022
+          12 | Plato         |          350 | 03-19-2022
+          14 | Smith         |          510 | 05-04-2022
+(11 rows)
+
+SELECT * FROM pg_indexes WHERE tablename = 'sales_others' and schemaname = 'partition_split_schema';
+       schemaname       |  tablename   |          indexname          | tablespace |                                                 indexdef                                                 
+------------------------+--------------+-----------------------------+------------+----------------------------------------------------------------------------------------------------------
+ partition_split_schema | sales_others | sales_others_sales_date_idx |            | CREATE INDEX sales_others_sales_date_idx ON partition_split_schema.sales_others USING btree (sales_date)
+(1 row)
+
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'),
+   PARTITION sales_others DEFAULT);
+-- Use indexscan for test indexes
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+SELECT * FROM sales_feb2022 where sales_date > '2022-01-01';
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+(3 rows)
+
+SELECT * FROM sales_mar2022 where sales_date > '2022-01-01';
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+(3 rows)
+
+SELECT * FROM sales_apr2022 where sales_date > '2022-01-01';
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          11 | Trump         |          380 | 04-06-2022
+           5 | Deev          |          250 | 04-07-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+(4 rows)
+
+SELECT * FROM sales_others where sales_date > '2022-01-01';
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          14 | Smith         |          510 | 05-04-2022
+(1 row)
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+SELECT * FROM pg_indexes WHERE tablename = 'sales_feb2022' and schemaname = 'partition_split_schema';
+       schemaname       |   tablename   |          indexname           | tablespace |                                                  indexdef                                                  
+------------------------+---------------+------------------------------+------------+------------------------------------------------------------------------------------------------------------
+ partition_split_schema | sales_feb2022 | sales_feb2022_sales_date_idx |            | CREATE INDEX sales_feb2022_sales_date_idx ON partition_split_schema.sales_feb2022 USING btree (sales_date)
+(1 row)
+
+SELECT * FROM pg_indexes WHERE tablename = 'sales_mar2022' and schemaname = 'partition_split_schema';
+       schemaname       |   tablename   |          indexname           | tablespace |                                                  indexdef                                                  
+------------------------+---------------+------------------------------+------------+------------------------------------------------------------------------------------------------------------
+ partition_split_schema | sales_mar2022 | sales_mar2022_sales_date_idx |            | CREATE INDEX sales_mar2022_sales_date_idx ON partition_split_schema.sales_mar2022 USING btree (sales_date)
+(1 row)
+
+SELECT * FROM pg_indexes WHERE tablename = 'sales_apr2022' and schemaname = 'partition_split_schema';
+       schemaname       |   tablename   |          indexname           | tablespace |                                                  indexdef                                                  
+------------------------+---------------+------------------------------+------------+------------------------------------------------------------------------------------------------------------
+ partition_split_schema | sales_apr2022 | sales_apr2022_sales_date_idx |            | CREATE INDEX sales_apr2022_sales_date_idx ON partition_split_schema.sales_apr2022 USING btree (sales_date)
+(1 row)
+
+SELECT * FROM pg_indexes WHERE tablename = 'sales_others' and schemaname = 'partition_split_schema';
+       schemaname       |  tablename   |          indexname           | tablespace |                                                 indexdef                                                  
+------------------------+--------------+------------------------------+------------+-----------------------------------------------------------------------------------------------------------
+ partition_split_schema | sales_others | sales_others_sales_date_idx1 |            | CREATE INDEX sales_others_sales_date_idx1 ON partition_split_schema.sales_others USING btree (sales_date)
+(1 row)
+
+DROP TABLE sales_range CASCADE;
+--
+-- Test: some cases for split DEFAULT partition (different bounds)
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date INT) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+-- sales_error intersects with sales_dec2022 (lower bound)
+-- ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20211230) TO (20220201),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+LINE 3:    PARTITION sales_error FOR VALUES FROM (20211230) TO (2022...
+                                                  ^
+-- sales_error intersects with sales_feb2022 (upper bound)
+-- ERROR:  lower bound of partition "sales_feb2022" conflicts with upper bound of previous partition "sales_error"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20220101) TO (20220202),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+ERROR:  lower bound of partition "sales_feb2022" conflicts with upper bound of previous partition "sales_error"
+LINE 4:    PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20...
+                                                    ^
+-- sales_error intersects with sales_dec2022 (inside bound)
+-- ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20211210) TO (20211220),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+LINE 3:    PARTITION sales_error FOR VALUES FROM (20211210) TO (2021...
+                                                  ^
+-- sales_error intersects with sales_dec2022 (exact the same bounds)
+-- ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+LINE 3:    PARTITION sales_error FOR VALUES FROM (20211201) TO (2022...
+                                                  ^
+-- ERROR:  any partition in the list should be DEFAULT because split partition is DEFAULT
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_jan2022 FOR VALUES FROM (20220101) TO (20220201),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301));
+ERROR:  any partition in the list should be DEFAULT because split partition is DEFAULT
+LINE 2:   (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20...
+                     ^
+-- no error: bounds of sales_noerror between sales_dec2022 and sales_feb2022
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_noerror FOR VALUES FROM (20220110) TO (20220120),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+DROP TABLE sales_range;
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date INT) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+-- no error: bounds of sales_noerror equals to lower and upper bounds of sales_dec2022 and sales_feb2022
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_noerror FOR VALUES FROM (20210101) TO (20210201),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+DROP TABLE sales_range;
+--
+-- Test: split partition with CHECK and FOREIGN KEY CONSTRAINTs on partitioned table
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30));
+INSERT INTO salesmans VALUES (1,  'Poirot');
+CREATE TABLE sales_range (
+salesman_id INT REFERENCES salesmans(salesman_id),
+sales_amount INT CHECK (sales_amount > 1),
+sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_feb_mar_apr2022'::regclass::oid;
+                    pg_get_constraintdef                     |            conname             | conkey 
+-------------------------------------------------------------+--------------------------------+--------
+ CHECK ((sales_amount > 1))                                  | sales_range_sales_amount_check | {2}
+ FOREIGN KEY (salesman_id) REFERENCES salesmans(salesman_id) | sales_range_salesman_id_fkey   | {1}
+(2 rows)
+
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+-- We should see the same CONSTRAINTs as on sales_feb_mar_apr2022 partition
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_feb2022'::regclass::oid;
+                    pg_get_constraintdef                     |            conname             | conkey 
+-------------------------------------------------------------+--------------------------------+--------
+ CHECK ((sales_amount > 1))                                  | sales_range_sales_amount_check | {2}
+ FOREIGN KEY (salesman_id) REFERENCES salesmans(salesman_id) | sales_range_salesman_id_fkey   | {1}
+(2 rows)
+
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_mar2022'::regclass::oid;
+                    pg_get_constraintdef                     |            conname             | conkey 
+-------------------------------------------------------------+--------------------------------+--------
+ CHECK ((sales_amount > 1))                                  | sales_range_sales_amount_check | {2}
+ FOREIGN KEY (salesman_id) REFERENCES salesmans(salesman_id) | sales_range_salesman_id_fkey   | {1}
+(2 rows)
+
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_apr2022'::regclass::oid;
+                    pg_get_constraintdef                     |            conname             | conkey 
+-------------------------------------------------------------+--------------------------------+--------
+ CHECK ((sales_amount > 1))                                  | sales_range_sales_amount_check | {2}
+ FOREIGN KEY (salesman_id) REFERENCES salesmans(salesman_id) | sales_range_salesman_id_fkey   | {1}
+(2 rows)
+
+-- ERROR:  new row for relation "sales_mar2022" violates check constraint "sales_range_salesman_id_check"
+INSERT INTO sales_range VALUES (1, 0, '2022-03-11');
+ERROR:  new row for relation "sales_mar2022" violates check constraint "sales_range_sales_amount_check"
+DETAIL:  Failing row contains (1, 0, 03-11-2022).
+-- ERROR:  insert or update on table "sales_mar2022" violates foreign key constraint "sales_range_salesman_id_fkey"
+INSERT INTO sales_range VALUES (-1, 10, '2022-03-11');
+ERROR:  insert or update on table "sales_mar2022" violates foreign key constraint "sales_range_salesman_id_fkey"
+DETAIL:  Key (salesman_id)=(-1) is not present in table "salesmans".
+-- ok
+INSERT INTO sales_range VALUES (1, 10, '2022-03-11');
+DROP TABLE sales_range CASCADE;
+DROP TABLE salesmans CASCADE;
+--
+-- Test: split partition on partitioned table in case exists FOREIGN KEY reference from another table
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+CREATE TABLE sales (salesman_id INT REFERENCES salesmans(salesman_id), sales_amount INT, sales_date DATE);
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+CREATE TABLE salesmans10_40 PARTITION OF salesmans FOR VALUES FROM (10) TO (40);
+INSERT INTO salesmans VALUES (1,  'Poirot');
+INSERT INTO salesmans VALUES (10, 'May');
+INSERT INTO salesmans VALUES (19, 'Ivanov');
+INSERT INTO salesmans VALUES (20, 'Smirnoff');
+INSERT INTO salesmans VALUES (30, 'Ford');
+INSERT INTO sales VALUES (1,  100, '2022-03-01');
+INSERT INTO sales VALUES (1,  110, '2022-03-02');
+INSERT INTO sales VALUES (10, 150, '2022-03-01');
+INSERT INTO sales VALUES (10, 90,  '2022-03-03');
+INSERT INTO sales VALUES (19, 200, '2022-03-04');
+INSERT INTO sales VALUES (20, 50,  '2022-03-12');
+INSERT INTO sales VALUES (20, 170, '2022-03-02');
+INSERT INTO sales VALUES (30, 30,  '2022-03-04');
+SELECT * FROM salesmans01_10;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+(1 row)
+
+SELECT * FROM salesmans10_40;
+ salesman_id | salesman_name 
+-------------+---------------
+          10 | May
+          19 | Ivanov
+          20 | Smirnoff
+          30 | Ford
+(4 rows)
+
+ALTER TABLE salesmans SPLIT PARTITION salesmans10_40 INTO
+  (PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20),
+   PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30),
+   PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40));
+SELECT * FROM salesmans01_10;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+(1 row)
+
+SELECT * FROM salesmans10_20;
+ salesman_id | salesman_name 
+-------------+---------------
+          10 | May
+          19 | Ivanov
+(2 rows)
+
+SELECT * FROM salesmans20_30;
+ salesman_id | salesman_name 
+-------------+---------------
+          20 | Smirnoff
+(1 row)
+
+SELECT * FROM salesmans30_40;
+ salesman_id | salesman_name 
+-------------+---------------
+          30 | Ford
+(1 row)
+
+-- ERROR:  insert or update on table "sales" violates foreign key constraint "sales_salesman_id_fkey"
+INSERT INTO sales VALUES (40, 50,  '2022-03-04');
+ERROR:  insert or update on table "sales" violates foreign key constraint "sales_salesman_id_fkey"
+DETAIL:  Key (salesman_id)=(40) is not present in table "salesmans".
+-- ok
+INSERT INTO sales VALUES (30, 50,  '2022-03-04');
+DROP TABLE sales CASCADE;
+DROP TABLE salesmans CASCADE;
+--
+-- Test: split partition of partitioned table with triggers
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+CREATE TABLE salesmans10_40 PARTITION OF salesmans FOR VALUES FROM (10) TO (40);
+INSERT INTO salesmans VALUES (1,  'Poirot');
+CREATE OR REPLACE FUNCTION after_insert_row_trigger() RETURNS trigger LANGUAGE 'plpgsql' AS $BODY$
+BEGIN
+	RAISE NOTICE 'trigger(%) called: action = %, when = %, level = %', TG_ARGV[0], TG_OP, TG_WHEN, TG_LEVEL;
+    RETURN NULL;
+END;
+$BODY$;
+CREATE TRIGGER salesmans_after_insert_statement_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+CREATE TRIGGER salesmans_after_insert_row_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH ROW
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (10, 'May');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = STATEMENT
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans10_40 VALUES (19, 'Ivanov');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+ALTER TABLE salesmans SPLIT PARTITION salesmans10_40 INTO
+  (PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20),
+   PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30),
+   PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40));
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (20, 'Smirnoff');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = STATEMENT
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans30_40 VALUES (30, 'Ford');
+NOTICE:  trigger(salesmans) called: action = INSERT, when = AFTER, level = ROW
+SELECT * FROM salesmans01_10;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+(1 row)
+
+SELECT * FROM salesmans10_20;
+ salesman_id | salesman_name 
+-------------+---------------
+          10 | May
+          19 | Ivanov
+(2 rows)
+
+SELECT * FROM salesmans20_30;
+ salesman_id | salesman_name 
+-------------+---------------
+          20 | Smirnoff
+(1 row)
+
+SELECT * FROM salesmans30_40;
+ salesman_id | salesman_name 
+-------------+---------------
+          30 | Ford
+(1 row)
+
+DROP TABLE salesmans CASCADE;
+DROP FUNCTION after_insert_row_trigger();
+--
+-- Test: split partition witch identity column
+-- If split partition column is identity-column, columns of new partitions are identity-columns too.
+--
+CREATE TABLE salesmans(salesman_id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+CREATE TABLE salesmans1_2 PARTITION OF salesmans FOR VALUES FROM (1) TO (2);
+-- Create new partition with identity-column:
+CREATE TABLE salesmans2_5(salesman_id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY, salesman_name VARCHAR(30));
+ALTER TABLE salesmans ATTACH PARTITION salesmans2_5 FOR VALUES FROM (2) TO (5);
+INSERT INTO salesmans (salesman_name) VALUES ('Poirot');
+INSERT INTO salesmans (salesman_name) VALUES ('Ivanov');
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   | a           | 
+ salesman_name |             | 
+(2 rows)
+
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans1_2'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   |             | 
+ salesman_name |             | 
+(2 rows)
+
+-- Split partition has identity-column:
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans2_5'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   | a           | 
+ salesman_name |             | 
+(2 rows)
+
+ALTER TABLE salesmans SPLIT PARTITION salesmans2_5 INTO
+  (PARTITION salesmans2_3 FOR VALUES FROM (2) TO (3),
+   PARTITION salesmans3_4 FOR VALUES FROM (3) TO (4),
+   PARTITION salesmans4_5 FOR VALUES FROM (4) TO (5));
+INSERT INTO salesmans (salesman_name) VALUES ('May');
+INSERT INTO salesmans (salesman_name) VALUES ('Ford');
+SELECT * FROM salesmans1_2;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+(1 row)
+
+SELECT * FROM salesmans2_3;
+ salesman_id | salesman_name 
+-------------+---------------
+           2 | Ivanov
+(1 row)
+
+SELECT * FROM salesmans3_4;
+ salesman_id | salesman_name 
+-------------+---------------
+           3 | May
+(1 row)
+
+SELECT * FROM salesmans4_5;
+ salesman_id | salesman_name 
+-------------+---------------
+           4 | Ford
+(1 row)
+
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   | a           | 
+ salesman_name |             | 
+(2 rows)
+
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans1_2'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   |             | 
+ salesman_name |             | 
+(2 rows)
+
+-- New partitions have identity-columns:
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans2_3'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   | a           | 
+ salesman_name |             | 
+(2 rows)
+
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans3_4'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   | a           | 
+ salesman_name |             | 
+(2 rows)
+
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans4_5'::regclass::oid;
+    attname    | attidentity | attgenerated 
+---------------+-------------+--------------
+ salesman_id   | a           | 
+ salesman_name |             | 
+(2 rows)
+
+DROP TABLE salesmans CASCADE;
+--
+-- Test: split partition with deleted columns
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+-- Create new partition with some deleted columns:
+CREATE TABLE salesmans10_40(d1 VARCHAR(30), salesman_id INT PRIMARY KEY, d2 INT, d3 DATE, salesman_name VARCHAR(30));
+INSERT INTO salesmans10_40 VALUES ('dummy value 1', 19, 100, now(), 'Ivanov');
+INSERT INTO salesmans10_40 VALUES ('dummy value 2', 20, 101, now(), 'Smirnoff');
+ALTER TABLE salesmans10_40 DROP COLUMN d1;
+ALTER TABLE salesmans10_40 DROP COLUMN d2;
+ALTER TABLE salesmans10_40 DROP COLUMN d3;
+ALTER TABLE salesmans ATTACH PARTITION salesmans10_40 FOR VALUES FROM (10) TO (40);
+INSERT INTO salesmans VALUES (1, 'Poirot');
+INSERT INTO salesmans VALUES (10, 'May');
+INSERT INTO salesmans VALUES (30, 'Ford');
+ALTER TABLE salesmans SPLIT PARTITION salesmans10_40 INTO
+  (PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20),
+   PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30),
+   PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40));
+select * from salesmans01_10;
+ salesman_id | salesman_name 
+-------------+---------------
+           1 | Poirot
+(1 row)
+
+select * from salesmans10_20;
+ salesman_id | salesman_name 
+-------------+---------------
+          19 | Ivanov
+          10 | May
+(2 rows)
+
+select * from salesmans20_30;
+ salesman_id | salesman_name 
+-------------+---------------
+          20 | Smirnoff
+(1 row)
+
+select * from salesmans30_40;
+ salesman_id | salesman_name 
+-------------+---------------
+          30 | Ford
+(1 row)
+
+DROP TABLE salesmans CASCADE;
+--
+-- Test: split sub-partition
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+CREATE TABLE sales_apr2022 (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_apr_all PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+ALTER TABLE sales_range ATTACH PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(4 rows)
+
+ALTER TABLE sales_apr2022 SPLIT PARTITION sales_apr_all INTO
+  (PARTITION sales_apr2022_01_10 FOR VALUES FROM ('2022-04-01') TO ('2022-04-10'),
+   PARTITION sales_apr2022_10_20 FOR VALUES FROM ('2022-04-10') TO ('2022-04-20'),
+   PARTITION sales_apr2022_20_30 FOR VALUES FROM ('2022-04-20') TO ('2022-05-01'));
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           3 | Ford          |         2000 | 04-30-2022
+(4 rows)
+
+SELECT * FROM sales_apr2022_01_10;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(2 rows)
+
+SELECT * FROM sales_apr2022_10_20;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           4 | Ivanov        |          750 | 04-13-2022
+(1 row)
+
+SELECT * FROM sales_apr2022_20_30;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           3 | Ford          |         2000 | 04-30-2022
+(1 row)
+
+DROP TABLE sales_range;
+--
+-- BY LIST partitioning
+--
+--
+-- Test: specific errors for BY LIST partitioning
+--
+CREATE TABLE sales_list
+(salesman_id INT,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_all PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Voronezh', 'Smolensk', 'Bryansk', 'Magadan', 'Kazan', 'Khabarovsk', 'Volgograd', 'Vladivostok');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+-- ERROR:  partition "sales_east" would overlap partition "sales_nord"
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok', 'Murmansk'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+ERROR:  new partition "sales_east" would overlap with another (not split) partition "sales_nord"
+LINE 3: ...ALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok', 'Murmansk'...
+                                                             ^
+-- ERROR:  new partition "sales_west" would overlap with another new partition "sales_central"
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Voronezh', 'Volgograd'));
+ERROR:  new partition "sales_west" would overlap with another new partition "sales_central"
+LINE 2:   (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk...
+                                               ^
+-- ERROR:  new partition "sales_west" cannot have NULL value because split partition does not have
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk', NULL),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+ERROR:  new partition "sales_west" cannot have NULL value because split partition does not have
+LINE 2: ...est FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk', NULL),
+                                                                 ^
+DROP TABLE sales_list;
+--
+-- Test: two specific errors for BY LIST partitioning:
+--   * new partitions not has NULL value that split partition has.
+--   * new partitions not has a value that split partition has.
+--
+CREATE TABLE sales_list
+(salesman_id INT,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_all PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Voronezh', 'Smolensk', 'Bryansk', 'Magadan', 'Kazan', 'Khabarovsk', 'Volgograd', 'Vladivostok', NULL);
+-- ERROR:  new partitions not have value NULL but split partition has
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+ERROR:  new partitions not have value NULL but split partition has
+-- ERROR:  new partitions not have value 'Volgograd' but split partition has
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', NULL));
+ERROR:  new partitions not have value 'Volgograd' but split partition has
+DROP TABLE sales_list;
+--
+-- Test: BY LIST partitioning, SPLIT PARTITION with data
+--
+CREATE TABLE sales_list
+(salesman_id INT GENERATED ALWAYS AS IDENTITY,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+CREATE INDEX sales_list_salesman_name_idx ON sales_list USING btree (salesman_name);
+CREATE INDEX sales_list_sales_state_idx ON sales_list USING btree (sales_state);
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_all PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Voronezh', 'Smolensk', 'Bryansk', 'Magadan', 'Kazan', 'Khabarovsk', 'Volgograd', 'Vladivostok');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Trump',    'Magadan',        1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smirnoff', 'Smolensk',       500,  '2022-03-03');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ford',     'St. Petersburg', 2000, '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ivanov',   'Moscow',         750,  '2022-03-04');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Deev',     'Voronezh',       250,  '2022-03-07');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Poirot',   'Kazan',          1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-06');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Li',       'Vladivostok',    1150, '2022-03-09');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-11');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Halder',   'Murmansk',       800,  '2022-03-02');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Muller',   'Bryansk',        650,  '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smith',    'Volgograd',      350,  '2022-03-10');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Gandi',    'Moscow',         150,  '2022-03-08');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Plato',    'Voronezh',       950,  '2022-03-05');
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+SELECT * FROM sales_list;
+ salesman_id | salesman_name |  sales_state   | sales_amount | sales_date 
+-------------+---------------+----------------+--------------+------------
+           2 | Smirnoff      | Smolensk       |          500 | 03-03-2022
+           5 | Deev          | Voronezh       |          250 | 03-07-2022
+          11 | Muller        | Bryansk        |          650 | 03-05-2022
+          14 | Plato         | Voronezh       |          950 | 03-05-2022
+           4 | Ivanov        | Moscow         |          750 | 03-04-2022
+           6 | Poirot        | Kazan          |         1000 | 03-01-2022
+          12 | Smith         | Volgograd      |          350 | 03-10-2022
+          13 | Gandi         | Moscow         |          150 | 03-08-2022
+           1 | Trump         | Magadan        |         1000 | 03-01-2022
+           8 | Li            | Vladivostok    |         1150 | 03-09-2022
+           3 | Ford          | St. Petersburg |         2000 | 03-05-2022
+           7 | May           | Ukhta          |         1200 | 03-06-2022
+           9 | May           | Ukhta          |         1200 | 03-11-2022
+          10 | Halder        | Murmansk       |          800 | 03-02-2022
+(14 rows)
+
+SELECT * FROM sales_west;
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           2 | Smirnoff      | Smolensk    |          500 | 03-03-2022
+           5 | Deev          | Voronezh    |          250 | 03-07-2022
+          11 | Muller        | Bryansk     |          650 | 03-05-2022
+          14 | Plato         | Voronezh    |          950 | 03-05-2022
+(4 rows)
+
+SELECT * FROM sales_east;
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           1 | Trump         | Magadan     |         1000 | 03-01-2022
+           8 | Li            | Vladivostok |         1150 | 03-09-2022
+(2 rows)
+
+SELECT * FROM sales_nord;
+ salesman_id | salesman_name |  sales_state   | sales_amount | sales_date 
+-------------+---------------+----------------+--------------+------------
+           3 | Ford          | St. Petersburg |         2000 | 03-05-2022
+           7 | May           | Ukhta          |         1200 | 03-06-2022
+           9 | May           | Ukhta          |         1200 | 03-11-2022
+          10 | Halder        | Murmansk       |          800 | 03-02-2022
+(4 rows)
+
+SELECT * FROM sales_central;
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+           6 | Poirot        | Kazan       |         1000 | 03-01-2022
+          12 | Smith         | Volgograd   |          350 | 03-10-2022
+          13 | Gandi         | Moscow      |          150 | 03-08-2022
+(4 rows)
+
+-- Use indexscan for test indexes after split partition
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+SELECT * FROM sales_central WHERE sales_state = 'Moscow';
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+          13 | Gandi         | Moscow      |          150 | 03-08-2022
+(2 rows)
+
+SELECT * FROM sales_list WHERE sales_state = 'Moscow';
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+          13 | Gandi         | Moscow      |          150 | 03-08-2022
+(2 rows)
+
+SELECT * FROM sales_list WHERE salesman_name = 'Ivanov';
+ salesman_id | salesman_name | sales_state | sales_amount | sales_date 
+-------------+---------------+-------------+--------------+------------
+           4 | Ivanov        | Moscow      |          750 | 03-04-2022
+(1 row)
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+DROP TABLE sales_list;
+--
+-- Test for:
+--   * split DEFAULT partition to partitions with spaces between bounds;
+--   * random order of partitions in SPLIT PARTITION command.
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-09');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-07');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_others DEFAULT,
+   PARTITION sales_mar2022_1decade FOR VALUES FROM ('2022-03-01') TO ('2022-03-10'),
+   PARTITION sales_jan2022_1decade FOR VALUES FROM ('2022-01-01') TO ('2022-01-10'),
+   PARTITION sales_feb2022_1decade FOR VALUES FROM ('2022-02-01') TO ('2022-02-10'),
+   PARTITION sales_apr2022_1decade FOR VALUES FROM ('2022-04-01') TO ('2022-04-10'));
+SELECT * FROM sales_jan2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          13 | Gandi         |          377 | 01-09-2022
+(1 row)
+
+SELECT * FROM sales_feb2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-09-2022
+           6 | Poirot        |          150 | 02-07-2022
+(2 rows)
+
+SELECT * FROM sales_mar2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           7 | Li            |          175 | 03-08-2022
+(1 row)
+
+SELECT * FROM sales_apr2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(2 rows)
+
+SELECT * FROM sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           9 | Muller        |          250 | 03-11-2022
+          10 | Halder        |          350 | 01-28-2022
+          12 | Plato         |          350 | 03-19-2022
+          14 | Smith         |          510 | 05-04-2022
+(8 rows)
+
+DROP TABLE sales_range;
+--
+-- Test for:
+--   * split non-DEFAULT partition to partitions with spaces between bounds;
+--   * random order of partitions in SPLIT PARTITION command.
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_all PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-09');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-07');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+ALTER TABLE sales_range SPLIT PARTITION sales_all INTO
+  (PARTITION sales_mar2022_1decade FOR VALUES FROM ('2022-03-01') TO ('2022-03-10'),
+   PARTITION sales_jan2022_1decade FOR VALUES FROM ('2022-01-01') TO ('2022-01-10'),
+   PARTITION sales_feb2022_1decade FOR VALUES FROM ('2022-02-01') TO ('2022-02-10'),
+   PARTITION sales_apr2022_1decade FOR VALUES FROM ('2022-04-01') TO ('2022-04-10'));
+SELECT * FROM sales_jan2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          13 | Gandi         |          377 | 01-09-2022
+(1 row)
+
+SELECT * FROM sales_feb2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-09-2022
+           6 | Poirot        |          150 | 02-07-2022
+(2 rows)
+
+SELECT * FROM sales_mar2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           7 | Li            |          175 | 03-08-2022
+(1 row)
+
+SELECT * FROM sales_apr2022_1decade;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(2 rows)
+
+SELECT * FROM sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+          14 | Smith         |          510 | 05-04-2022
+           1 | May           |         1000 | 01-31-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           9 | Muller        |          250 | 03-11-2022
+          10 | Halder        |          350 | 01-28-2022
+          12 | Plato         |          350 | 03-19-2022
+(8 rows)
+
+DROP TABLE sales_range;
+--
+-- Test for split non-DEFAULT partition to DEFAULT partition + partitions
+-- with spaces between bounds.
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_all PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+ALTER TABLE sales_range SPLIT PARTITION sales_all INTO
+  (PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'),
+   PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_others DEFAULT);
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+SELECT * FROM sales_range;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+          14 | Smith         |          510 | 05-04-2022
+(14 rows)
+
+SELECT * FROM sales_jan2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           1 | May           |         1000 | 01-31-2022
+          10 | Halder        |          350 | 01-28-2022
+          13 | Gandi         |          377 | 01-09-2022
+(3 rows)
+
+SELECT * FROM sales_feb2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           2 | Smirnoff      |          500 | 02-10-2022
+           6 | Poirot        |          150 | 02-11-2022
+           8 | Ericsson      |          185 | 02-23-2022
+(3 rows)
+
+SELECT * FROM sales_apr2022;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           3 | Ford          |         2000 | 04-30-2022
+           4 | Ivanov        |          750 | 04-13-2022
+           5 | Deev          |          250 | 04-07-2022
+          11 | Trump         |          380 | 04-06-2022
+(4 rows)
+
+SELECT * FROM sales_others;
+ salesman_id | salesman_name | sales_amount | sales_date 
+-------------+---------------+--------------+------------
+           7 | Li            |          175 | 03-08-2022
+           9 | Muller        |          250 | 03-11-2022
+          12 | Plato         |          350 | 03-19-2022
+          14 | Smith         |          510 | 05-04-2022
+(4 rows)
+
+DROP TABLE sales_range;
+--
+DROP SCHEMA partition_split_schema;
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index 41fa8e93c5..80608597e5 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -119,7 +119,7 @@ test: plancache limit plpgsql copy2 temp domain rangefuncs prepare conversion tr
 # The stats test resets stats, so nothing else needing stats access can be in
 # this group.
 # ----------
-test: partition_merge partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats
+test: partition_merge partition_split partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats
 
 # event_trigger cannot run concurrently with any test that runs DDL
 # oidjoins is read-only, though, and should run late for best coverage
diff --git a/src/test/regress/sql/partition_split.sql b/src/test/regress/sql/partition_split.sql
new file mode 100644
index 0000000000..58e17f33e8
--- /dev/null
+++ b/src/test/regress/sql/partition_split.sql
@@ -0,0 +1,833 @@
+--
+-- PARTITION_SPLIT
+-- Tests for "ALTER TABLE ... SPLIT PARTITION ..." command
+--
+
+CREATE SCHEMA partition_split_schema;
+SET search_path = partition_split_schema, public;
+
+--
+-- BY RANGE partitioning
+--
+
+--
+-- Test for error codes
+--
+CREATE TABLE sales_range (salesman_id int, salesman_name varchar(30), sales_amount int, sales_date date) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+-- ERROR:  relation "sales_xxx" does not exist
+ALTER TABLE sales_range SPLIT PARTITION sales_xxx INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- ERROR:  relation "sales_jan2022" already exists
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- ERROR:  invalid bound specification for a range partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES IN ('2022-05-01', '2022-06-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- ERROR:  empty range bound specified for partition "sales_mar2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-02-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+--ERROR:  list of split partitions should contains at least two items
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-10-01'));
+
+-- ERROR:  lower bound of partition "sales_feb2022" is less than lower bound of split partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-01-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- ERROR:  name "sales_feb_mar_apr2022" already used
+-- (We can create partition with the same name as split partition, but can't create two partitions with the same name)
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb_mar_apr2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_feb_mar_apr2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- ERROR:  name "sales_feb2022" already used
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_feb2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- ERROR:  "sales_feb_mar_apr2022" is not a partitioned table
+ALTER TABLE sales_feb_mar_apr2022 SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_feb2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- ERROR:  upper bound of partition "sales_apr2022" is greater than upper bound of split partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-06-01'));
+
+-- ERROR:  lower bound of partition "sales_mar2022" is not equals to upper bound of previous partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-02-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- Tests for spaces between partitions, them should be executed without DEFAULT partition
+ALTER TABLE sales_range DETACH PARTITION sales_others;
+
+-- ERROR:  lower bound of partition "sales_feb2022" is not equals to lower bound of split partition
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-02') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+DROP TABLE sales_range;
+DROP TABLE sales_others;
+
+--
+-- Add rows into partitioned table then split partition
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_jan2022;
+SELECT * FROM sales_feb2022;
+SELECT * FROM sales_mar2022;
+SELECT * FROM sales_apr2022;
+SELECT * FROM sales_others;
+
+DROP TABLE sales_range CASCADE;
+
+--
+-- Add split partition then add rows into partitioned table
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_jan2022;
+SELECT * FROM sales_feb2022;
+SELECT * FROM sales_mar2022;
+SELECT * FROM sales_apr2022;
+SELECT * FROM sales_others;
+
+DROP TABLE sales_range CASCADE;
+
+--
+-- Test for:
+--   * composite partition key;
+--   * GENERATED column;
+--   * column with DEFAULT value.
+--
+CREATE TABLE sales_date (salesman_name VARCHAR(30), sales_year INT, sales_month INT, sales_day INT,
+  sales_date VARCHAR(10) GENERATED ALWAYS AS
+    (LPAD(sales_year::text, 4, '0') || '.' || LPAD(sales_month::text, 2, '0') || '.' || LPAD(sales_day::text, 2, '0')) STORED,
+  sales_department VARCHAR(30) DEFAULT 'Sales department')
+  PARTITION BY RANGE (sales_year, sales_month, sales_day);
+
+CREATE TABLE sales_dec2022 PARTITION OF sales_date FOR VALUES FROM (2021, 12, 1) TO (2022, 1, 1);
+CREATE TABLE sales_jan_feb2022 PARTITION OF sales_date FOR VALUES FROM (2022, 1, 1) TO (2022, 3, 1);
+CREATE TABLE sales_other PARTITION OF sales_date FOR VALUES FROM (2022, 3, 1) TO (MAXVALUE, MAXVALUE, MAXVALUE);
+
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2021, 12, 7);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2021, 12, 8);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 1, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 2, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 1, 2);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 2, 1);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 3, 3);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 3, 4);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager3', 2022, 5, 1);
+
+SELECT * FROM sales_date;
+SELECT * FROM sales_dec2022;
+SELECT * FROM sales_jan_feb2022;
+SELECT * FROM sales_other;
+
+ALTER TABLE sales_date SPLIT PARTITION sales_jan_feb2022 INTO
+  (PARTITION sales_jan2022 FOR VALUES FROM (2022, 1, 1) TO (2022, 2, 1),
+   PARTITION sales_feb2022 FOR VALUES FROM (2022, 2, 1) TO (2022, 3, 1));
+
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager1', 2022, 1, 10);
+INSERT INTO sales_date(salesman_name, sales_year, sales_month, sales_day) VALUES ('Manager2', 2022, 2, 10);
+
+SELECT * FROM sales_date;
+SELECT * FROM sales_dec2022;
+SELECT * FROM sales_jan2022;
+SELECT * FROM sales_feb2022;
+SELECT * FROM sales_other;
+
+--ERROR:  relation "sales_jan_feb2022" does not exist
+SELECT * FROM sales_jan_feb2022;
+
+DROP TABLE sales_date CASCADE;
+
+--
+-- Test: split DEFAULT partition; using a index on partition key; check index after split
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+SELECT * FROM sales_others;
+SELECT * FROM pg_indexes WHERE tablename = 'sales_others' and schemaname = 'partition_split_schema';
+
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'),
+   PARTITION sales_others DEFAULT);
+
+-- Use indexscan for test indexes
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+
+SELECT * FROM sales_feb2022 where sales_date > '2022-01-01';
+SELECT * FROM sales_mar2022 where sales_date > '2022-01-01';
+SELECT * FROM sales_apr2022 where sales_date > '2022-01-01';
+SELECT * FROM sales_others where sales_date > '2022-01-01';
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+
+SELECT * FROM pg_indexes WHERE tablename = 'sales_feb2022' and schemaname = 'partition_split_schema';
+SELECT * FROM pg_indexes WHERE tablename = 'sales_mar2022' and schemaname = 'partition_split_schema';
+SELECT * FROM pg_indexes WHERE tablename = 'sales_apr2022' and schemaname = 'partition_split_schema';
+SELECT * FROM pg_indexes WHERE tablename = 'sales_others' and schemaname = 'partition_split_schema';
+
+DROP TABLE sales_range CASCADE;
+
+--
+-- Test: some cases for split DEFAULT partition (different bounds)
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date INT) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+-- sales_error intersects with sales_dec2022 (lower bound)
+-- ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20211230) TO (20220201),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+
+-- sales_error intersects with sales_feb2022 (upper bound)
+-- ERROR:  lower bound of partition "sales_feb2022" conflicts with upper bound of previous partition "sales_error"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20220101) TO (20220202),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+
+-- sales_error intersects with sales_dec2022 (inside bound)
+-- ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20211210) TO (20211220),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+
+-- sales_error intersects with sales_dec2022 (exact the same bounds)
+-- ERROR:  lower bound of partition "sales_error" conflicts with upper bound of previous partition "sales_dec2022"
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_error FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+
+-- ERROR:  any partition in the list should be DEFAULT because split partition is DEFAULT
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_jan2022 FOR VALUES FROM (20220101) TO (20220201),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301));
+
+-- no error: bounds of sales_noerror between sales_dec2022 and sales_feb2022
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_noerror FOR VALUES FROM (20220110) TO (20220120),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+
+DROP TABLE sales_range;
+
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date INT) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+-- no error: bounds of sales_noerror equals to lower and upper bounds of sales_dec2022 and sales_feb2022
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_dec2022 FOR VALUES FROM (20211201) TO (20220101),
+   PARTITION sales_noerror FOR VALUES FROM (20210101) TO (20210201),
+   PARTITION sales_feb2022 FOR VALUES FROM (20220201) TO (20220301),
+   PARTITION sales_others DEFAULT);
+
+DROP TABLE sales_range;
+
+--
+-- Test: split partition with CHECK and FOREIGN KEY CONSTRAINTs on partitioned table
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30));
+INSERT INTO salesmans VALUES (1,  'Poirot');
+
+CREATE TABLE sales_range (
+salesman_id INT REFERENCES salesmans(salesman_id),
+sales_amount INT CHECK (sales_amount > 1),
+sales_date DATE) PARTITION BY RANGE (sales_date);
+
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb_mar_apr2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_feb_mar_apr2022'::regclass::oid;
+
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2022 INTO
+  (PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_mar2022 FOR VALUES FROM ('2022-03-01') TO ('2022-04-01'),
+   PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'));
+
+-- We should see the same CONSTRAINTs as on sales_feb_mar_apr2022 partition
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_feb2022'::regclass::oid;
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_mar2022'::regclass::oid;
+SELECT pg_get_constraintdef(oid), conname, conkey FROM pg_constraint WHERE conrelid = 'sales_apr2022'::regclass::oid;
+
+-- ERROR:  new row for relation "sales_mar2022" violates check constraint "sales_range_salesman_id_check"
+INSERT INTO sales_range VALUES (1, 0, '2022-03-11');
+-- ERROR:  insert or update on table "sales_mar2022" violates foreign key constraint "sales_range_salesman_id_fkey"
+INSERT INTO sales_range VALUES (-1, 10, '2022-03-11');
+-- ok
+INSERT INTO sales_range VALUES (1, 10, '2022-03-11');
+
+DROP TABLE sales_range CASCADE;
+DROP TABLE salesmans CASCADE;
+
+--
+-- Test: split partition on partitioned table in case exists FOREIGN KEY reference from another table
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+CREATE TABLE sales (salesman_id INT REFERENCES salesmans(salesman_id), sales_amount INT, sales_date DATE);
+
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+CREATE TABLE salesmans10_40 PARTITION OF salesmans FOR VALUES FROM (10) TO (40);
+
+INSERT INTO salesmans VALUES (1,  'Poirot');
+INSERT INTO salesmans VALUES (10, 'May');
+INSERT INTO salesmans VALUES (19, 'Ivanov');
+INSERT INTO salesmans VALUES (20, 'Smirnoff');
+INSERT INTO salesmans VALUES (30, 'Ford');
+
+INSERT INTO sales VALUES (1,  100, '2022-03-01');
+INSERT INTO sales VALUES (1,  110, '2022-03-02');
+INSERT INTO sales VALUES (10, 150, '2022-03-01');
+INSERT INTO sales VALUES (10, 90,  '2022-03-03');
+INSERT INTO sales VALUES (19, 200, '2022-03-04');
+INSERT INTO sales VALUES (20, 50,  '2022-03-12');
+INSERT INTO sales VALUES (20, 170, '2022-03-02');
+INSERT INTO sales VALUES (30, 30,  '2022-03-04');
+
+SELECT * FROM salesmans01_10;
+SELECT * FROM salesmans10_40;
+
+ALTER TABLE salesmans SPLIT PARTITION salesmans10_40 INTO
+  (PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20),
+   PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30),
+   PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40));
+
+SELECT * FROM salesmans01_10;
+SELECT * FROM salesmans10_20;
+SELECT * FROM salesmans20_30;
+SELECT * FROM salesmans30_40;
+
+-- ERROR:  insert or update on table "sales" violates foreign key constraint "sales_salesman_id_fkey"
+INSERT INTO sales VALUES (40, 50,  '2022-03-04');
+-- ok
+INSERT INTO sales VALUES (30, 50,  '2022-03-04');
+
+DROP TABLE sales CASCADE;
+DROP TABLE salesmans CASCADE;
+
+--
+-- Test: split partition of partitioned table with triggers
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+CREATE TABLE salesmans10_40 PARTITION OF salesmans FOR VALUES FROM (10) TO (40);
+
+INSERT INTO salesmans VALUES (1,  'Poirot');
+
+CREATE OR REPLACE FUNCTION after_insert_row_trigger() RETURNS trigger LANGUAGE 'plpgsql' AS $BODY$
+BEGIN
+	RAISE NOTICE 'trigger(%) called: action = %, when = %, level = %', TG_ARGV[0], TG_OP, TG_WHEN, TG_LEVEL;
+    RETURN NULL;
+END;
+$BODY$;
+
+CREATE TRIGGER salesmans_after_insert_statement_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+
+CREATE TRIGGER salesmans_after_insert_row_trigger
+    AFTER INSERT
+    ON salesmans
+    FOR EACH ROW
+    EXECUTE PROCEDURE after_insert_row_trigger('salesmans');
+
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (10, 'May');
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans10_40 VALUES (19, 'Ivanov');
+
+ALTER TABLE salesmans SPLIT PARTITION salesmans10_40 INTO
+  (PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20),
+   PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30),
+   PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40));
+
+-- 2 triggers should fire here (row + statement):
+INSERT INTO salesmans VALUES (20, 'Smirnoff');
+-- 1 trigger should fire here (row):
+INSERT INTO salesmans30_40 VALUES (30, 'Ford');
+
+SELECT * FROM salesmans01_10;
+SELECT * FROM salesmans10_20;
+SELECT * FROM salesmans20_30;
+SELECT * FROM salesmans30_40;
+
+DROP TABLE salesmans CASCADE;
+DROP FUNCTION after_insert_row_trigger();
+
+--
+-- Test: split partition witch identity column
+-- If split partition column is identity-column, columns of new partitions are identity-columns too.
+--
+CREATE TABLE salesmans(salesman_id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+
+CREATE TABLE salesmans1_2 PARTITION OF salesmans FOR VALUES FROM (1) TO (2);
+-- Create new partition with identity-column:
+CREATE TABLE salesmans2_5(salesman_id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY, salesman_name VARCHAR(30));
+ALTER TABLE salesmans ATTACH PARTITION salesmans2_5 FOR VALUES FROM (2) TO (5);
+
+INSERT INTO salesmans (salesman_name) VALUES ('Poirot');
+INSERT INTO salesmans (salesman_name) VALUES ('Ivanov');
+
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans'::regclass::oid;
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans1_2'::regclass::oid;
+-- Split partition has identity-column:
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans2_5'::regclass::oid;
+
+ALTER TABLE salesmans SPLIT PARTITION salesmans2_5 INTO
+  (PARTITION salesmans2_3 FOR VALUES FROM (2) TO (3),
+   PARTITION salesmans3_4 FOR VALUES FROM (3) TO (4),
+   PARTITION salesmans4_5 FOR VALUES FROM (4) TO (5));
+
+INSERT INTO salesmans (salesman_name) VALUES ('May');
+INSERT INTO salesmans (salesman_name) VALUES ('Ford');
+
+SELECT * FROM salesmans1_2;
+SELECT * FROM salesmans2_3;
+SELECT * FROM salesmans3_4;
+SELECT * FROM salesmans4_5;
+
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans'::regclass::oid;
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans1_2'::regclass::oid;
+-- New partitions have identity-columns:
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans2_3'::regclass::oid;
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans3_4'::regclass::oid;
+SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans4_5'::regclass::oid;
+
+DROP TABLE salesmans CASCADE;
+
+--
+-- Test: split partition with deleted columns
+--
+CREATE TABLE salesmans(salesman_id INT PRIMARY KEY, salesman_name VARCHAR(30)) PARTITION BY RANGE (salesman_id);
+
+CREATE TABLE salesmans01_10 PARTITION OF salesmans FOR VALUES FROM (1) TO (10);
+-- Create new partition with some deleted columns:
+CREATE TABLE salesmans10_40(d1 VARCHAR(30), salesman_id INT PRIMARY KEY, d2 INT, d3 DATE, salesman_name VARCHAR(30));
+
+INSERT INTO salesmans10_40 VALUES ('dummy value 1', 19, 100, now(), 'Ivanov');
+INSERT INTO salesmans10_40 VALUES ('dummy value 2', 20, 101, now(), 'Smirnoff');
+
+ALTER TABLE salesmans10_40 DROP COLUMN d1;
+ALTER TABLE salesmans10_40 DROP COLUMN d2;
+ALTER TABLE salesmans10_40 DROP COLUMN d3;
+
+ALTER TABLE salesmans ATTACH PARTITION salesmans10_40 FOR VALUES FROM (10) TO (40);
+
+INSERT INTO salesmans VALUES (1, 'Poirot');
+INSERT INTO salesmans VALUES (10, 'May');
+INSERT INTO salesmans VALUES (30, 'Ford');
+
+ALTER TABLE salesmans SPLIT PARTITION salesmans10_40 INTO
+  (PARTITION salesmans10_20 FOR VALUES FROM (10) TO (20),
+   PARTITION salesmans20_30 FOR VALUES FROM (20) TO (30),
+   PARTITION salesmans30_40 FOR VALUES FROM (30) TO (40));
+
+select * from salesmans01_10;
+select * from salesmans10_20;
+select * from salesmans20_30;
+select * from salesmans30_40;
+
+DROP TABLE salesmans CASCADE;
+
+--
+-- Test: split sub-partition
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_feb2022 PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-03-01');
+CREATE TABLE sales_mar2022 PARTITION OF sales_range FOR VALUES FROM ('2022-03-01') TO ('2022-04-01');
+
+CREATE TABLE sales_apr2022 (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_apr_all PARTITION OF sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+ALTER TABLE sales_range ATTACH PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01');
+
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+CREATE INDEX sales_range_sales_date_idx ON sales_range USING btree (sales_date);
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_apr2022;
+
+ALTER TABLE sales_apr2022 SPLIT PARTITION sales_apr_all INTO
+  (PARTITION sales_apr2022_01_10 FOR VALUES FROM ('2022-04-01') TO ('2022-04-10'),
+   PARTITION sales_apr2022_10_20 FOR VALUES FROM ('2022-04-10') TO ('2022-04-20'),
+   PARTITION sales_apr2022_20_30 FOR VALUES FROM ('2022-04-20') TO ('2022-05-01'));
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_apr2022;
+SELECT * FROM sales_apr2022_01_10;
+SELECT * FROM sales_apr2022_10_20;
+SELECT * FROM sales_apr2022_20_30;
+
+DROP TABLE sales_range;
+
+--
+-- BY LIST partitioning
+--
+
+--
+-- Test: specific errors for BY LIST partitioning
+--
+CREATE TABLE sales_list
+(salesman_id INT,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_all PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Voronezh', 'Smolensk', 'Bryansk', 'Magadan', 'Kazan', 'Khabarovsk', 'Volgograd', 'Vladivostok');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+
+-- ERROR:  partition "sales_east" would overlap partition "sales_nord"
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok', 'Murmansk'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+
+-- ERROR:  new partition "sales_west" would overlap with another new partition "sales_central"
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Voronezh', 'Volgograd'));
+
+-- ERROR:  new partition "sales_west" cannot have NULL value because split partition does not have
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk', NULL),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+
+DROP TABLE sales_list;
+
+--
+-- Test: two specific errors for BY LIST partitioning:
+--   * new partitions not has NULL value that split partition has.
+--   * new partitions not has a value that split partition has.
+--
+CREATE TABLE sales_list
+(salesman_id INT,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_all PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Voronezh', 'Smolensk', 'Bryansk', 'Magadan', 'Kazan', 'Khabarovsk', 'Volgograd', 'Vladivostok', NULL);
+
+-- ERROR:  new partitions not have value NULL but split partition has
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+
+-- ERROR:  new partitions not have value 'Volgograd' but split partition has
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', NULL));
+
+DROP TABLE sales_list;
+
+--
+-- Test: BY LIST partitioning, SPLIT PARTITION with data
+--
+CREATE TABLE sales_list
+(salesman_id INT GENERATED ALWAYS AS IDENTITY,
+ salesman_name VARCHAR(30),
+ sales_state VARCHAR(20),
+ sales_amount INT,
+ sales_date DATE)
+PARTITION BY LIST (sales_state);
+
+CREATE INDEX sales_list_salesman_name_idx ON sales_list USING btree (salesman_name);
+CREATE INDEX sales_list_sales_state_idx ON sales_list USING btree (sales_state);
+
+CREATE TABLE sales_nord PARTITION OF sales_list FOR VALUES IN ('Murmansk', 'St. Petersburg', 'Ukhta');
+CREATE TABLE sales_all PARTITION OF sales_list FOR VALUES IN ('Moscow', 'Voronezh', 'Smolensk', 'Bryansk', 'Magadan', 'Kazan', 'Khabarovsk', 'Volgograd', 'Vladivostok');
+CREATE TABLE sales_others PARTITION OF sales_list DEFAULT;
+
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Trump',    'Magadan',        1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smirnoff', 'Smolensk',       500,  '2022-03-03');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ford',     'St. Petersburg', 2000, '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Ivanov',   'Moscow',         750,  '2022-03-04');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Deev',     'Voronezh',       250,  '2022-03-07');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Poirot',   'Kazan',          1000, '2022-03-01');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-06');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Li',       'Vladivostok',    1150, '2022-03-09');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('May',      'Ukhta',          1200, '2022-03-11');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Halder',   'Murmansk',       800,  '2022-03-02');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Muller',   'Bryansk',        650,  '2022-03-05');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Smith',    'Volgograd',      350,  '2022-03-10');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Gandi',    'Moscow',         150,  '2022-03-08');
+INSERT INTO sales_list (salesman_name, sales_state, sales_amount, sales_date) VALUES ('Plato',    'Voronezh',       950,  '2022-03-05');
+
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+  (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+   PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+   PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+
+SELECT * FROM sales_list;
+SELECT * FROM sales_west;
+SELECT * FROM sales_east;
+SELECT * FROM sales_nord;
+SELECT * FROM sales_central;
+
+-- Use indexscan for test indexes after split partition
+SET enable_indexscan = ON;
+SET enable_seqscan = OFF;
+
+SELECT * FROM sales_central WHERE sales_state = 'Moscow';
+SELECT * FROM sales_list WHERE sales_state = 'Moscow';
+SELECT * FROM sales_list WHERE salesman_name = 'Ivanov';
+
+SET enable_indexscan = ON;
+SET enable_seqscan = ON;
+
+DROP TABLE sales_list;
+
+--
+-- Test for:
+--   * split DEFAULT partition to partitions with spaces between bounds;
+--   * random order of partitions in SPLIT PARTITION command.
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-09');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-07');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+ALTER TABLE sales_range SPLIT PARTITION sales_others INTO
+  (PARTITION sales_others DEFAULT,
+   PARTITION sales_mar2022_1decade FOR VALUES FROM ('2022-03-01') TO ('2022-03-10'),
+   PARTITION sales_jan2022_1decade FOR VALUES FROM ('2022-01-01') TO ('2022-01-10'),
+   PARTITION sales_feb2022_1decade FOR VALUES FROM ('2022-02-01') TO ('2022-02-10'),
+   PARTITION sales_apr2022_1decade FOR VALUES FROM ('2022-04-01') TO ('2022-04-10'));
+
+SELECT * FROM sales_jan2022_1decade;
+SELECT * FROM sales_feb2022_1decade;
+SELECT * FROM sales_mar2022_1decade;
+SELECT * FROM sales_apr2022_1decade;
+SELECT * FROM sales_others;
+
+DROP TABLE sales_range;
+
+--
+-- Test for:
+--   * split non-DEFAULT partition to partitions with spaces between bounds;
+--   * random order of partitions in SPLIT PARTITION command.
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_all PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-05-01');
+CREATE TABLE sales_others PARTITION OF sales_range DEFAULT;
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-09');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-07');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+ALTER TABLE sales_range SPLIT PARTITION sales_all INTO
+  (PARTITION sales_mar2022_1decade FOR VALUES FROM ('2022-03-01') TO ('2022-03-10'),
+   PARTITION sales_jan2022_1decade FOR VALUES FROM ('2022-01-01') TO ('2022-01-10'),
+   PARTITION sales_feb2022_1decade FOR VALUES FROM ('2022-02-01') TO ('2022-02-10'),
+   PARTITION sales_apr2022_1decade FOR VALUES FROM ('2022-04-01') TO ('2022-04-10'));
+
+SELECT * FROM sales_jan2022_1decade;
+SELECT * FROM sales_feb2022_1decade;
+SELECT * FROM sales_mar2022_1decade;
+SELECT * FROM sales_apr2022_1decade;
+SELECT * FROM sales_others;
+
+DROP TABLE sales_range;
+
+--
+-- Test for split non-DEFAULT partition to DEFAULT partition + partitions
+-- with spaces between bounds.
+--
+CREATE TABLE sales_range (salesman_id INT, salesman_name VARCHAR(30), sales_amount INT, sales_date DATE) PARTITION BY RANGE (sales_date);
+CREATE TABLE sales_jan2022 PARTITION OF sales_range FOR VALUES FROM ('2022-01-01') TO ('2022-02-01');
+CREATE TABLE sales_all PARTITION OF sales_range FOR VALUES FROM ('2022-02-01') TO ('2022-05-01');
+
+INSERT INTO sales_range VALUES (1,  'May',      1000, '2022-01-31');
+INSERT INTO sales_range VALUES (2,  'Smirnoff', 500,  '2022-02-10');
+INSERT INTO sales_range VALUES (3,  'Ford',     2000, '2022-04-30');
+INSERT INTO sales_range VALUES (4,  'Ivanov',   750,  '2022-04-13');
+INSERT INTO sales_range VALUES (5,  'Deev',     250,  '2022-04-07');
+INSERT INTO sales_range VALUES (6,  'Poirot',   150,  '2022-02-11');
+INSERT INTO sales_range VALUES (7,  'Li',       175,  '2022-03-08');
+INSERT INTO sales_range VALUES (8,  'Ericsson', 185,  '2022-02-23');
+INSERT INTO sales_range VALUES (9,  'Muller',   250,  '2022-03-11');
+INSERT INTO sales_range VALUES (10, 'Halder',   350,  '2022-01-28');
+INSERT INTO sales_range VALUES (11, 'Trump',    380,  '2022-04-06');
+INSERT INTO sales_range VALUES (12, 'Plato',    350,  '2022-03-19');
+INSERT INTO sales_range VALUES (13, 'Gandi',    377,  '2022-01-09');
+
+ALTER TABLE sales_range SPLIT PARTITION sales_all INTO
+  (PARTITION sales_apr2022 FOR VALUES FROM ('2022-04-01') TO ('2022-05-01'),
+   PARTITION sales_feb2022 FOR VALUES FROM ('2022-02-01') TO ('2022-03-01'),
+   PARTITION sales_others DEFAULT);
+
+INSERT INTO sales_range VALUES (14, 'Smith',    510,  '2022-05-04');
+
+SELECT * FROM sales_range;
+SELECT * FROM sales_jan2022;
+SELECT * FROM sales_feb2022;
+SELECT * FROM sales_apr2022;
+SELECT * FROM sales_others;
+
+DROP TABLE sales_range;
+
+--
+DROP SCHEMA partition_split_schema;
-- 
2.31.0.windows.1

From 28c0c7d37fc86e9d2584771813a06281bd72d5f9 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Tue, 28 Mar 2023 10:50:19 +0300
Subject: [PATCH v17 3/3] Documentation for ALTER TABLE SPLIT PARTITION/MERGE
 PARTITIONS commands

---
 doc/src/sgml/ref/alter_table.sgml | 124 +++++++++++++++++++++++++++++-
 1 file changed, 121 insertions(+), 3 deletions(-)

diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index d4d93eeb7c..1480e30c18 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -37,6 +37,13 @@ ALTER TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
     ATTACH PARTITION <replaceable class="parameter">partition_name</replaceable> { FOR VALUES <replaceable class="parameter">partition_bound_spec</replaceable> | DEFAULT }
 ALTER TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
     DETACH PARTITION <replaceable class="parameter">partition_name</replaceable> [ CONCURRENTLY | FINALIZE ]
+ALTER TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
+    SPLIT PARTITION <replaceable class="parameter">partition_name</replaceable> INTO
+        (PARTITION <replaceable class="parameter">partition_name1</replaceable> { FOR VALUES <replaceable class="parameter">partition_bound_spec</replaceable> | DEFAULT },
+         PARTITION <replaceable class="parameter">partition_name2</replaceable> { FOR VALUES <replaceable class="parameter">partition_bound_spec</replaceable> | DEFAULT } [, ...])
+ALTER TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceable>
+    MERGE PARTITIONS (<replaceable class="parameter">partition_name1</replaceable>, <replaceable class="parameter">partition_name2</replaceable> [, ...])
+        INTO <replaceable class="parameter">partition_name</replaceable>
 
 <phrase>where <replaceable class="parameter">action</replaceable> is one of:</phrase>
 
@@ -1091,14 +1098,99 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
     </listitem>
    </varlistentry>
 
+   <varlistentry id="sql-altertable-split-partition">
+    <term><literal>SPLIT PARTITION <replaceable class="parameter">partition_name</replaceable> INTO (PARTITION <replaceable class="parameter">partition_name1</replaceable> { FOR VALUES <replaceable class="parameter">partition_bound_spec</replaceable> | DEFAULT }, PARTITION <replaceable class="parameter">partition_name2</replaceable> { FOR VALUES <replaceable class="parameter">partition_bound_spec</replaceable> | DEFAULT } [, ...])</literal></term>
+
+    <listitem>
+     <para>
+      This form split a single partition of the target table. Hash-partitioning
+      is not supported. Bounds of new partitions should not overlap with new and
+      existing partitions (except <replaceable class="parameter">partition_name</replaceable>).
+      If the split partition is DEFAULT partition, one of new partitions must be DEFAULT.
+      In case one of new partitions or one of existing partitions is DEFAULT,
+      new partitions <replaceable class="parameter">partition_name1</replaceable>,
+      <replaceable class="parameter">partition_name2</replaceable>, ... can have spaces
+      between partitions bounds.  If the partitioned table does not have a DEFAULT
+      partition, the DEFAULT partition can be defined as one of the new partitions.
+     </para>
+     <para>
+      In case new partitions do not contains DEFAULT partition and the partitioned table
+      does not have a DEFAULT partition, the following must be true: sum bounds of
+      new partitions <replaceable class="parameter">partition_name1</replaceable>,
+      <replaceable class="parameter">partition_name2</replaceable>, ... should be
+      equal to bound of split partition <replaceable class="parameter">partition_name</replaceable>.
+      One of the new partitions <replaceable class="parameter">partition_name1</replaceable>,
+      <replaceable class="parameter">partition_name2</replaceable>, ... can have
+      the same name as split partition <replaceable class="parameter">partition_name</replaceable>
+      (this is suitable in case of splitting a DEFAULT partition: we split it, but after
+      splitting we have a partition with the same name).
+      Only simple, non-partitioned partition can be split.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry id="sql-altertable-merge-partitions">
+    <term><literal>MERGE PARTITIONS (<replaceable class="parameter">partition_name1</replaceable>, <replaceable class="parameter">partition_name2</replaceable> [, ...]) INTO <replaceable class="parameter">partition_name</replaceable></literal></term>
+
+    <listitem>
+     <para>
+      This form merge several partitions into one partition of the target table.
+      Hash-partitioning is not supported.  If DEFAULT partition is not in the
+      list of partitions <replaceable class="parameter">partition_name1</replaceable>,
+      <replaceable class="parameter">partition_name2</replaceable> [, ...]:
+      <itemizedlist>
+       <listitem>
+        <para>
+         For range-partitioned tables is necessary that the ranges
+         of the partitions <replaceable class="parameter">partition_name1</replaceable>,
+         <replaceable class="parameter">partition_name2</replaceable> [, ...] can
+         be merged into one range without spaces and overlaps (otherwise an error
+         will be generated).  The combined range will be the range for the partition
+         <replaceable class="parameter">partition_name</replaceable>.
+        </para>
+       </listitem>
+       <listitem>
+        <para>
+         For list-partitioned tables the values lists of all partitions
+         <replaceable class="parameter">partition_name1</replaceable>,
+         <replaceable class="parameter">partition_name2</replaceable> [, ...] are
+         combined and form a list of values of partition
+         <replaceable class="parameter">partition_name</replaceable>.
+        </para>
+       </listitem>
+      </itemizedlist>
+      If DEFAULT partition is in the list of partitions <replaceable class="parameter">partition_name1</replaceable>,
+      <replaceable class="parameter">partition_name2</replaceable> [, ...]:
+      <itemizedlist>
+       <listitem>
+        <para>
+         The partition <replaceable class="parameter">partition_name</replaceable>
+         will be the DEFAULT partition.
+        </para>
+       </listitem>
+       <listitem>
+        <para>
+         For range- and list-partitioned tables the ranges and lists of values
+         of the merged partitions can be any.
+        </para>
+       </listitem>
+      </itemizedlist>
+      The new partition <replaceable class="parameter">partition_name</replaceable>
+      can have the same name as one of the merged partitions.  Only simple,
+      non-partitioned partitions can be merged.
+     </para>
+    </listitem>
+   </varlistentry>
+
   </variablelist>
   </para>
 
   <para>
    All the forms of ALTER TABLE that act on a single table, except
    <literal>RENAME</literal>, <literal>SET SCHEMA</literal>,
-   <literal>ATTACH PARTITION</literal>, and
-   <literal>DETACH PARTITION</literal> can be combined into
+   <literal>ATTACH PARTITION</literal>, <literal>DETACH PARTITION</literal>,
+   <literal>SPLIT PARTITION</literal>, and <literal>MERGE PARTITIONS</literal>
+   can be combined into
    a list of multiple alterations to be applied together.  For example, it
    is possible to add several columns and/or alter the type of several
    columns in a single command.  This is particularly useful with large
@@ -1341,7 +1433,8 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
       <term><replaceable class="parameter">partition_name</replaceable></term>
       <listitem>
        <para>
-        The name of the table to attach as a new partition or to detach from this table.
+        The name of the table to attach as a new partition or to detach from this table,
+        or the name of split partition, or the name of the new merged partition.
        </para>
       </listitem>
      </varlistentry>
@@ -1757,6 +1850,31 @@ ALTER TABLE measurement
     DETACH PARTITION measurement_y2015m12;
 </programlisting></para>
 
+  <para>
+   To split a single partition of the range-partitioned table:
+<programlisting>
+ALTER TABLE sales_range SPLIT PARTITION sales_feb_mar_apr2023 INTO
+   (PARTITION sales_feb2023 FOR VALUES FROM ('2023-02-01') TO ('2023-03-01'),
+    PARTITION sales_mar2023 FOR VALUES FROM ('2023-03-01') TO ('2023-04-01'),
+    PARTITION sales_apr2023 FOR VALUES FROM ('2023-04-01') TO ('2023-05-01'));
+</programlisting></para>
+
+  <para>
+   To split a single partition of the list-partitioned table:
+<programlisting>
+ALTER TABLE sales_list SPLIT PARTITION sales_all INTO
+   (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
+    PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
+    PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+</programlisting></para>
+
+  <para>
+   To merge several partitions into one partition of the target table:
+<programlisting>
+ALTER TABLE sales_list MERGE PARTITIONS (sales_west, sales_east, sales_central)
+    INTO sales_all;
+</programlisting></para>
+
  </refsect1>
 
  <refsect1>
-- 
2.31.0.windows.1

---

From: Daniel Gustafsson <[email-masked]>
Date: Thu, 6 Jul 2023 18:10:28 +0200

This patch no longer applies to master, please submit a rebased version to the
thread. I've marked the CF entry as waiting for author in the meantime.

--
Daniel Gustafsson

---

From: Dmitry Koval <[email-masked]>
Date: Thu, 6 Jul 2023 21:43:23 +0300

Thanks, Daniel!

 > This patch no longer applies to master, please submit a rebased
 > version to the thread.

Here is a rebased version.

-- 
With best regards,
Dmitry Koval

From fa9372301410eed180ddead4a3ff595e1acc77bf Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 16:06:03 +0300
Subject: [PATCH v18 1/3] ALTER TABLE MERGE PARTITIONS command

---

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index fce5e6f220..a62abe128d 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -640,6 +640,8 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);

 /* ----------------------------------------------------------------
  *		DefineRelation
@@ -4493,6 +4495,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;

 				/*
@@ -4914,6 +4920,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			/* No command-specific prep needed */
 			pass = AT_PASS_MISC;
 			break;
+		case AT_MergePartitions:
+			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
+			/* No command-specific prep needed */
+			pass = AT_PASS_MISC;
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -5301,6 +5312,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
 		case AT_DetachPartitionFinalize:
 			address = ATExecDetachPartitionFinalize(rel, ((PartitionCmd *) cmd->def)->name);
 			break;
+		case AT_MergePartitions:
+			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
+									  cur_pass, context);
+			Assert(cmd != NULL);
+			Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
+			ATExecMergePartitions(wqueue, tab, rel, (PartitionCmd *) cmd->def,
+								  context);
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -6284,6 +6303,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
 			return "DETACH PARTITION";
 		case AT_DetachPartitionFinalize:
 			return "DETACH PARTITION ... FINALIZE";
+		case AT_MergePartitions:
+			return "MERGE PARTITIONS";
 		case AT_AddIdentity:
 			return "ALTER COLUMN ... ADD IDENTITY";
 		case AT_SetIdentity:
@@ -17701,6 +17722,37 @@ QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
 	}
 }
 
+/*
@@ -17893,23 +17945,8 @@ ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd,

 	/*
 	 * Generate partition constraint from the partition bound specification.
@@ -19394,3 +19431,283 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 
 	return cstorage;
 }
+
+/*
index 39ab7eac0d..ac8b121f97 100644
@@ -745,7 +745,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -2287,6 +2287,7 @@ partition_cmd:
 
@@ -2301,6 +2302,7 @@ partition_cmd:
 					n->subtype = AT_DetachPartition;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
 					cmd->concurrent = $4;
 					n->def = (Node *) cmd;
 
@@ -2314,6 +2316,21 @@ partition_cmd:
@@ -2330,6 +2347,7 @@ index_partition_cmd:
 
@@ -17128,6 +17146,7 @@ unreserved_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLANS
@@ -17724,6 +17743,7 @@ bare_label_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLACING
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index d67580fc77..1cc5048c9e 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -58,6 +58,8 @@
 #include "parser/parse_type.h"
 #include "parser/parse_utilcmd.h"
 #include "parser/parser.h"
+#include "partitioning/partdesc.h"
+#include "partitioning/partbounds.h"
 #include "rewrite/rewriteManip.h"
 #include "utils/acl.h"
 #include "utils/builtins.h"
@@ -3264,6 +3266,80 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3533,6 +3609,19 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,

 				/*
index 7c5d9110fb..7e4ab9eca6 100644
 
index 88b03cc472..6f2c1693b4 100644
 
+/*
 
@@ -2235,6 +2247,7 @@ typedef enum AlterTableType
index f5b2e61ca5..a61b9e922b 100644
@@ -322,6 +322,7 @@ PG_KEYWORD("parameter", PARAMETER, UNRESERVED_KEYWORD, BARE_LABEL)
 
index 82f937fca4..216ed3c47f 100644
index cf46fa3359..6ed44fbbae 100644
 
index e941fb6c82..68faaf2606 100644
@@ -2552,6 +2552,7 @@ SimpleStats
 SimpleStringList
 SimpleStringListCell
 SingleBoundSortItem
+SinglePartitionSpec
 Size
 SkipPages
 SlabBlock
-- 
2.40.1.windows.1

From 379171c4cd2cee6f49c516ef0f73110ae2e5cd24 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 17:58:52 +0300
Subject: [PATCH v18 2/3] ALTER TABLE SPLIT PARTITION command

---

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index a62abe128d..0fe9fbe705 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -640,6 +640,9 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);

@@ -4495,6 +4498,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
@@ -4920,6 +4927,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
@@ -5312,6 +5324,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
@@ -6303,6 +6323,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
@@ -19432,6 +19454,255 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 	return cstorage;
 }
 
+/*
@@ -19486,6 +19757,142 @@ createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
 				   NULL);
 }
 
+/*
index ac8b121f97..01da2ee775 100644
@@ -270,6 +270,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
@@ -642,6 +643,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -760,7 +763,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	SAVEPOINT SCALAR SCHEMA SCHEMAS SCROLL SEARCH SECOND_P SECURITY SELECT
 	SEQUENCE SEQUENCES
 	SERIALIZABLE SERVER SESSION SESSION_USER SET SETS SETOF SHARE SHOW
-	SIMILAR SIMPLE SKIP SMALLINT SNAPSHOT SOME SQL_P STABLE STANDALONE_P
+	SIMILAR SIMPLE SKIP SMALLINT SNAPSHOT SOME SPLIT SQL_P STABLE STANDALONE_P
 	START STATEMENT STATISTICS STDIN STDOUT STORAGE STORED STRICT_P STRIP_P
 	SUBSCRIPTION SUBSTRING SUPPORT SYMMETRIC SYSID SYSTEM_P SYSTEM_USER
 
@@ -2277,6 +2280,23 @@ alter_table_cmds:
 			| alter_table_cmds ',' alter_table_cmd	{ $$ = lappend($1, $3); }
 		;
 
+partitions_list:
+			SinglePartitionSpec							{ $$ = list_make1($1); }
+			| partitions_list ',' SinglePartitionSpec	{ $$ = lappend($1, $3); }
+		;
+
+SinglePartitionSpec:
+			PARTITION qualified_name PartitionBoundSpec
+				{
+					SinglePartitionSpec *n = makeNode(SinglePartitionSpec);
+
+					n->name = $2;
+					n->bound = $3;
+
+					$$ = n;
+				}
+		;
+
 partition_cmd:
 			/* ALTER TABLE <name> ATTACH PARTITION <table_name> FOR VALUES */
 			ATTACH PARTITION qualified_name PartitionBoundSpec
@@ -2321,6 +2341,20 @@ partition_cmd:
 					n->def = (Node *) cmd;
 					$$ = (Node *) n;
 				}
+			/* ALTER TABLE <name> SPLIT PARTITION <partition_name> INTO () */
+			| SPLIT PARTITION qualified_name INTO '(' partitions_list ')'
+				{
+					AlterTableCmd *n = makeNode(AlterTableCmd);
+					PartitionCmd *cmd = makeNode(PartitionCmd);
+
+					n->subtype = AT_SplitPartition;
+					cmd->name = $3;
+					cmd->bound = NULL;
+					cmd->partlist = $6;
+					cmd->concurrent = false;
+					n->def = (Node *) cmd;
+					$$ = (Node *) n;
+				}
 			/* ALTER TABLE <name> MERGE PARTITIONS () INTO <partition_name> */
 			| MERGE PARTITIONS '(' qualified_name_list ')' INTO qualified_name
 				{
@@ -17211,6 +17245,7 @@ unreserved_keyword:
 			| SIMPLE
 			| SKIP
 			| SNAPSHOT
+			| SPLIT
 			| SQL_P
 			| STABLE
 			| STANDALONE_P
@@ -17820,6 +17855,7 @@ bare_label_keyword:
 			| SMALLINT
 			| SNAPSHOT
 			| SOME
+			| SPLIT
 			| SQL_P
 			| STABLE
 			| STANDALONE_P
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 1cc5048c9e..7aff987204 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -135,7 +135,7 @@ static void transformConstraintAttrs(CreateStmtContext *cxt,
 									 List *constraintList);
 static void transformColumnType(CreateStmtContext *cxt, ColumnDef *column);
 static void setSchemaName(const char *context_schema, char **stmt_schema_name);
-static void transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd);
+static void transformPartitionCmd(CreateStmtContext *cxt, PartitionBoundSpec *bound);
 static List *transformPartitionRangeBounds(ParseState *pstate, List *blist,
 										   Relation parent);
 static void validateInfiniteBounds(ParseState *pstate, List *blist);
@@ -3266,6 +3266,43 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3601,7 +3638,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3609,6 +3646,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3617,7 +3655,11 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
@@ -4015,13 +4057,13 @@ setSchemaName(const char *context_schema, char **stmt_schema_name)
 
 /*
  * transformPartitionCmd
 
@@ -4030,9 +4072,9 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 
@@ -4040,7 +4082,7 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
index 7e4ab9eca6..8aec8d69ce 100644
 
+/*
 
+/*
index d3a973d86b..1984b244cc 100644
@@ -12606,3 +12606,21 @@ get_range_partbound_string(List *bound_datums)
 
 	return buf->data;
 }
+
+/*
index 6f2c1693b4..ba9e3d9700 100644
@@ -2247,6 +2247,7 @@ typedef enum AlterTableType
index a61b9e922b..8d7d3c428d 100644
@@ -402,6 +402,7 @@ PG_KEYWORD("skip", SKIP, UNRESERVED_KEYWORD, BARE_LABEL)
 
+extern void check_partitions_for_split(Relation parent,
+									   Oid splitPartOid,
+									   RangeVar *splitPartName,
+									   List *partlist,
+									   ParseState *pstate);
 extern void calculate_partition_bound_for_merge(Relation parent,
 												List *partNames,
 												List *partOids,
diff --git a/src/include/utils/ruleutils.h b/src/include/utils/ruleutils.h
index b006d9d475..0e4a8a4047 100644
--- a/src/include/utils/ruleutils.h
+++ b/src/include/utils/ruleutils.h
@@ -49,4 +49,6 @@ extern char *get_range_partbound_string(List *bound_datums);

index 216ed3c47f..324a95b35f 100644
index 6ed44fbbae..0b632221b6 100644
 
2.40.1.windows.1

From d0236d733ca9578183b64b4ed4cc2dfff887c669 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Tue, 28 Mar 2023 10:50:19 +0300
Subject: [PATCH v18 3/3] Documentation for ALTER TABLE SPLIT PARTITION/MERGE
 PARTITIONS commands

---

 

   <para>
 
+  <para>
 
  <refsect1>
-- 
2.40.1.windows.1

---

From: stephane tachoires <[email-masked]>
Date: Tue, 18 Jul 2023 12:51:41 +0000

The following review has been posted through the commitfest application:
make installcheck-world:  not tested
Implements feature:       not tested
Spec compliant:           not tested
Documentation:            not tested

Only documentation patch applied on 4e465aac36ce9a9533c68dbdc83e67579880e628
Checked with v18

The new status of this patch is: Waiting on Author

---

From: Dmitry Koval <[email-masked]>
Date: Wed, 19 Jul 2023 16:43:47 +0300

Thank you, Stephane!

Rebased version attached to email.

-- 
With best regards,
Dmitry Koval

From 7a472ec572fb7c83431c153b9e27b54bb2a9493c Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 16:06:03 +0300
Subject: [PATCH v19 1/3] ALTER TABLE MERGE PARTITIONS command

---

index 4dc029f91f..203432dfb1 100644

 /* ----------------------------------------------------------------
  *		DefineRelation
@@ -4492,6 +4494,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;

 				/*
@@ -4913,6 +4919,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			/* No command-specific prep needed */
 			pass = AT_PASS_MISC;
 			break;
+		case AT_MergePartitions:
+			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
+			/* No command-specific prep needed */
+			pass = AT_PASS_MISC;
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -5300,6 +5311,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
 		case AT_DetachPartitionFinalize:
 			address = ATExecDetachPartitionFinalize(rel, ((PartitionCmd *) cmd->def)->name);
 			break;
+		case AT_MergePartitions:
+			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
+									  cur_pass, context);
+			Assert(cmd != NULL);
+			Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
+			ATExecMergePartitions(wqueue, tab, rel, (PartitionCmd *) cmd->def,
+								  context);
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -6283,6 +6302,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
 			return "DETACH PARTITION";
 		case AT_DetachPartitionFinalize:
 			return "DETACH PARTITION ... FINALIZE";
+		case AT_MergePartitions:
+			return "MERGE PARTITIONS";
 		case AT_AddIdentity:
 			return "ALTER COLUMN ... ADD IDENTITY";
 		case AT_SetIdentity:
@@ -17698,6 +17719,37 @@ QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
 	}
 }
 
+/*
@@ -17890,23 +17942,8 @@ ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd,

 	/*
 	 * Generate partition constraint from the partition bound specification.
@@ -19398,3 +19435,283 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 
 	return cstorage;
 }
+
+/*
index edb6c00ece..cb90f15948 100644
@@ -742,7 +742,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -2284,6 +2284,7 @@ partition_cmd:
 
@@ -2298,6 +2299,7 @@ partition_cmd:
 					n->subtype = AT_DetachPartition;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
 					cmd->concurrent = $4;
 					n->def = (Node *) cmd;
 
@@ -2311,6 +2313,21 @@ partition_cmd:
@@ -2327,6 +2344,7 @@ index_partition_cmd:
 
@@ -17125,6 +17143,7 @@ unreserved_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLANS
@@ -17721,6 +17740,7 @@ bare_label_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLACING
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index e48e9e99d3..f23e1e2930 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -58,6 +58,8 @@
 #include "parser/parse_type.h"
 #include "parser/parse_utilcmd.h"
 #include "parser/parser.h"
+#include "partitioning/partdesc.h"
+#include "partitioning/partbounds.h"
 #include "rewrite/rewriteManip.h"
 #include "utils/acl.h"
 #include "utils/builtins.h"
@@ -3258,6 +3260,80 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3527,6 +3603,19 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,

 				/*
 
index efb5c3e098..712f39f50b 100644
@@ -931,6 +931,17 @@ typedef struct PartitionRangeDatum
 
+/*
@@ -939,6 +950,7 @@ typedef struct PartitionCmd
 
@@ -2234,6 +2246,7 @@ typedef enum AlterTableType
 
index 4df9d8503b..fa02a704c1 100644
 
 # event_trigger depends on create_am and cannot run concurrently with
 # any test that runs DDL

From c00a16a51ff6cb27594afcf6f15cccaabbe48d8d Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 17:58:52 +0300
Subject: [PATCH v19 2/3] ALTER TABLE SPLIT PARTITION command

---

index 203432dfb1..07a0266d1b 100644

@@ -4494,6 +4497,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
@@ -4919,6 +4926,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
@@ -5311,6 +5323,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
@@ -6302,6 +6322,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
@@ -19436,6 +19458,255 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 	return cstorage;
 }
 
+/*
@@ -19490,6 +19761,142 @@ createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
 				   NULL);
 }
 
+/*
index cb90f15948..642e019e7b 100644
 
@@ -757,7 +760,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -2274,6 +2277,23 @@ alter_table_cmds:
 			| alter_table_cmds ',' alter_table_cmd	{ $$ = lappend($1, $3); }
 		;
 
+partitions_list:
@@ -2318,6 +2338,20 @@ partition_cmd:
@@ -17208,6 +17242,7 @@ unreserved_keyword:
@@ -17817,6 +17852,7 @@ bare_label_keyword:
index f23e1e2930..8de45df453 100644
@@ -3260,6 +3260,43 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3595,7 +3632,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3603,6 +3640,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3611,7 +3649,11 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
@@ -4009,13 +4051,13 @@ setSchemaName(const char *context_schema, char **stmt_schema_name)
 
 /*
  * transformPartitionCmd
 
@@ -4024,9 +4066,9 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 
@@ -4034,7 +4076,7 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 
+/*
 
+/*
 
 	return buf->data;
 }
+
+/*
index 712f39f50b..00667a7210 100644
@@ -2246,6 +2246,7 @@ typedef enum AlterTableType

 
index fa02a704c1..7f29eef9d6 100644
 
 # event_trigger depends on create_am and cannot run concurrently with
 # any test that runs DDL

From 818666b451a2306c4af3ce5b40e1f0c9d76d395f Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Tue, 28 Mar 2023 10:50:19 +0300
Subject: [PATCH v19 3/3] Documentation for ALTER TABLE SPLIT PARTITION/MERGE
 PARTITIONS commands

---

 

   <para>
 
+  <para>
 
  <refsect1>
-- 
2.40.1.windows.1

---

From: stephane tachoires <[email-masked]>
Date: Thu, 20 Jul 2023 11:56:33 +0000

Documentation:            tested, passed

It is just a rebase
I check with make and meson
run manual split and merge on list and range partition
Doc fits

The new status of this patch is: Ready for Committer

---

From: Dmitry Koval <[email-masked]>
Date: Sat, 11 Nov 2023 13:26:03 +0300

-- 
With best regards,
Dmitry Koval

From dab0c597e8abdb43d7d2c404284ccfcd96b2e443 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 16:06:03 +0300
Subject: [PATCH v20 1/3] ALTER TABLE MERGE PARTITIONS command

---

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index e456ccd767..f02b8a9dbe 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -650,6 +650,8 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, const char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);

 /* ----------------------------------------------------------------
  *		DefineRelation
@@ -4679,6 +4681,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
+			case AT_MergePartitions:
+				cmd_lockmode = AccessExclusiveLock;
+				break;
+
 			default:			/* oops */
 				elog(ERROR, "unrecognized alter table type: %d",
 					 (int) cmd->subtype);
@@ -5093,6 +5099,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			/* No command-specific prep needed */
 			pass = AT_PASS_MISC;
 			break;
+		case AT_MergePartitions:
+			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
+			/* No command-specific prep needed */
+			pass = AT_PASS_MISC;
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -5481,6 +5492,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
 		case AT_DetachPartitionFinalize:
 			address = ATExecDetachPartitionFinalize(rel, ((PartitionCmd *) cmd->def)->name);
 			break;
+		case AT_MergePartitions:
+			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
+									  cur_pass, context);
+			Assert(cmd != NULL);
+			Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
+			ATExecMergePartitions(wqueue, tab, rel, (PartitionCmd *) cmd->def,
+								  context);
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -6467,6 +6486,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
 			return "DETACH PARTITION";
 		case AT_DetachPartitionFinalize:
 			return "DETACH PARTITION ... FINALIZE";
+		case AT_MergePartitions:
+			return "MERGE PARTITIONS";
 		case AT_AddIdentity:
 			return "ALTER COLUMN ... ADD IDENTITY";
 		case AT_SetIdentity:
@@ -18492,6 +18513,37 @@ QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
 	}
 }
 
+/*
+ * attachPartitionTable: attach new partition to partitioned table
+ *
+ * wqueue: the ALTER TABLE work queue; can be NULL when not running as part
+ *   of an ALTER TABLE sequence.
+ * rel: partitioned relation;
+ * attachrel: relation of attached partition;
+ * bound: bounds of attached relation.
+ */
+static void
+attachPartitionTable(List **wqueue, Relation rel, Relation attachrel, PartitionBoundSpec *bound)
+{
+	/* OK to create inheritance.  Rest of the checks performed there */
+	CreateInheritance(attachrel, rel);
+
+	/* Update the pg_class entry. */
+	StorePartitionBound(attachrel, rel, bound);
+
+	/* Ensure there exists a correct set of indexes in the partition. */
+	AttachPartitionEnsureIndexes(wqueue, rel, attachrel);
+
+	/* and triggers */
+	CloneRowTriggersToPartition(rel, attachrel);
+
+	/*
+	 * Clone foreign key constraints.  Callee is responsible for setting up
+	 * for phase 3 constraint verification.
+	 */
+	CloneForeignKeyConstraints(wqueue, rel, attachrel);
+}
+
 /*
  * ALTER TABLE <name> ATTACH PARTITION <partition-name> FOR VALUES
  *
@@ -18684,23 +18736,8 @@ ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd,
 	check_new_partition_bound(RelationGetRelationName(attachrel), rel,
 							  cmd->bound, pstate);
 
-	AttachPartitionEnsureIndexes(wqueue, rel, attachrel);
 
 	/*
 	 * Generate partition constraint from the partition bound specification.
@@ -20242,3 +20279,283 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 
 	return cstorage;
 }
+
+/*
index c224df4ecc..242b8c2715 100644
@@ -743,7 +743,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -2285,6 +2285,7 @@ partition_cmd:
 
@@ -2299,6 +2300,7 @@ partition_cmd:
 					n->subtype = AT_DetachPartition;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
 					cmd->concurrent = $4;
 					n->def = (Node *) cmd;
 
@@ -2312,6 +2314,21 @@ partition_cmd:
@@ -2328,6 +2345,7 @@ index_partition_cmd:
 
@@ -17257,6 +17275,7 @@ unreserved_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLANS
@@ -17858,6 +17877,7 @@ bare_label_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLACING
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index cf0d432ab1..6c4dc3f1b1 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -58,6 +58,8 @@
 #include "parser/parse_type.h"
 #include "parser/parse_utilcmd.h"
 #include "parser/parser.h"
+#include "partitioning/partdesc.h"
+#include "partitioning/partbounds.h"
 #include "rewrite/rewriteManip.h"
 #include "utils/acl.h"
 #include "utils/builtins.h"
@@ -3378,6 +3380,80 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3648,6 +3724,19 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,

 				/*
index 9f207b44c3..213289f515 100644
 
index e494309da8..31b6e2ab24 100644
@@ -924,6 +924,17 @@ typedef struct PartitionRangeDatum
 
+/*
@@ -932,6 +943,7 @@ typedef struct PartitionCmd
 
@@ -2247,6 +2259,7 @@ typedef enum AlterTableType
index 5984dcfa4b..f76a7c3023 100644
@@ -324,6 +324,7 @@ PG_KEYWORD("parameter", PARAMETER, UNRESERVED_KEYWORD, BARE_LABEL)
index 53bcc867df..7b95bb73b0 100644
 
index b2be88ead1..1071256182 100644
@@ -103,6 +103,7 @@ test: partition-key-update-1
index 0302f79bb7..0bdcd2e617 100644
index f0987ff537..42cfeab20c 100644
 
index bf50a32119..5251db5fad 100644
@@ -2563,6 +2563,7 @@ SimpleStats
 SimpleStringList
 SimpleStringListCell
 SingleBoundSortItem
+SinglePartitionSpec
 Size
 SkipPages
 SlabBlock
-- 
2.40.1.windows.1

From e3914255ad86e9bc48507d4a479d35f99267a43d Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 17:58:52 +0300
Subject: [PATCH v20 2/3] ALTER TABLE SPLIT PARTITION command

---

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index f02b8a9dbe..f779d9b62b 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -650,6 +650,9 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, const char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);

@@ -4681,6 +4684,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
@@ -5099,6 +5106,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
@@ -5492,6 +5504,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
@@ -6486,6 +6506,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
@@ -20280,6 +20302,255 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 	return cstorage;
 }
 
+/*
@@ -20334,6 +20605,142 @@ createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
 				   NULL);
 }
 
+/*
index 242b8c2715..796ad1c124 100644
 
@@ -758,7 +761,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -2275,6 +2278,23 @@ alter_table_cmds:
 			| alter_table_cmds ',' alter_table_cmd	{ $$ = lappend($1, $3); }
 		;
 
+partitions_list:
+			SinglePartitionSpec							{ $$ = list_make1($1); }
+			| partitions_list ',' SinglePartitionSpec	{ $$ = lappend($1, $3); }
+		;
+
+SinglePartitionSpec:
+			PARTITION qualified_name PartitionBoundSpec
+				{
+					SinglePartitionSpec *n = makeNode(SinglePartitionSpec);
+
+					n->name = $2;
+					n->bound = $3;
+
+					$$ = n;
+				}
+		;
+
 partition_cmd:
 			/* ALTER TABLE <name> ATTACH PARTITION <table_name> FOR VALUES */
 			ATTACH PARTITION qualified_name PartitionBoundSpec
@@ -2319,6 +2339,20 @@ partition_cmd:
 					n->def = (Node *) cmd;
 					$$ = (Node *) n;
 				}
+			/* ALTER TABLE <name> SPLIT PARTITION <partition_name> INTO () */
+			| SPLIT PARTITION qualified_name INTO '(' partitions_list ')'
+				{
+					AlterTableCmd *n = makeNode(AlterTableCmd);
+					PartitionCmd *cmd = makeNode(PartitionCmd);
+
+					n->subtype = AT_SplitPartition;
+					cmd->name = $3;
+					cmd->bound = NULL;
+					cmd->partlist = $6;
+					cmd->concurrent = false;
+					n->def = (Node *) cmd;
+					$$ = (Node *) n;
+				}
 			/* ALTER TABLE <name> MERGE PARTITIONS () INTO <partition_name> */
 			| MERGE PARTITIONS '(' qualified_name_list ')' INTO qualified_name
 				{
@@ -17340,6 +17374,7 @@ unreserved_keyword:
 			| SIMPLE
 			| SKIP
 			| SNAPSHOT
+			| SPLIT
 			| SQL_P
 			| STABLE
 			| STANDALONE_P
@@ -17954,6 +17989,7 @@ bare_label_keyword:
 			| SMALLINT
 			| SNAPSHOT
 			| SOME
+			| SPLIT
 			| SQL_P
 			| STABLE
 			| STANDALONE_P
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 6c4dc3f1b1..de1b3a773b 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -136,7 +136,7 @@ static void transformConstraintAttrs(CreateStmtContext *cxt,
 									 List *constraintList);
 static void transformColumnType(CreateStmtContext *cxt, ColumnDef *column);
 static void setSchemaName(const char *context_schema, char **stmt_schema_name);
-static void transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd);
+static void transformPartitionCmd(CreateStmtContext *cxt, PartitionBoundSpec *bound);
 static List *transformPartitionRangeBounds(ParseState *pstate, List *blist,
 										   Relation parent);
 static void validateInfiniteBounds(ParseState *pstate, List *blist);
@@ -3380,6 +3380,43 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3716,7 +3753,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3724,6 +3761,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3732,7 +3770,11 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
@@ -4137,13 +4179,13 @@ setSchemaName(const char *context_schema, char **stmt_schema_name)
 
 /*
  * transformPartitionCmd
 
@@ -4152,9 +4194,9 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 
@@ -4162,7 +4204,7 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
index 213289f515..d64d724099 100644
 
+/*
 
+/*
index ed7f40f053..26f81a32fa 100644
@@ -12651,3 +12651,21 @@ get_range_partbound_string(List *bound_datums)
 
 	return buf->data;
 }
+
+/*
index 31b6e2ab24..6acaeccebc 100644
@@ -2259,6 +2259,7 @@ typedef enum AlterTableType
index f76a7c3023..b54ebbb786 100644
@@ -404,6 +404,7 @@ PG_KEYWORD("skip", SKIP, UNRESERVED_KEYWORD, BARE_LABEL)
index 7b95bb73b0..67a1f94763 100644

 
index 1071256182..79b730fb86 100644
@@ -104,6 +104,7 @@ test: partition-key-update-2
index 0bdcd2e617..f7258968b1 100644
index 42cfeab20c..fb90d988ff 100644

From 6f2f3c495453a4af8aaaae3a11108f7c8cebdfa3 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Tue, 28 Mar 2023 10:50:19 +0300
Subject: [PATCH v20 3/3] Documentation for ALTER TABLE SPLIT PARTITION/MERGE
 PARTITIONS commands

---

index 2c4138e4e9..17be88a53d 100644

@@ -1092,14 +1099,99 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
     </listitem>
    </varlistentry>

   <para>
@@ -1342,7 +1434,8 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
@@ -1758,6 +1851,31 @@ ALTER TABLE measurement
 
+  <para>
 
  <refsect1>
-- 
2.40.1.windows.1

---

From: Dmitry Koval <[email-masked]>
Date: Mon, 4 Dec 2023 10:52:06 +0300

Hello!

Added commit v21-0004-SPLIT-PARTITION-optimization.patch.

Three already existing commits did not change 
(v21-0001-ALTER-TABLE-MERGE-PARTITIONS-command.patch, 
v21-0002-ALTER-TABLE-SPLIT-PARTITION-command.patch, 
v21-0003-Documentation-for-ALTER-TABLE-SPLIT-PARTITION-ME.patch).

The new commit is an optimization for the SPLIT PARTITION command.

Description of optimization:
1) optimization is used for the SPLIT PARTITION command for tables with 
BY RANGE partitioning in case the partitioning key has a b-tree index;
2) the point of optimization is that, if after dividing of the old 
partition, all its records according to the range conditions must be 
inserted into ONE new partition, then instead of transferring data (from 
the old partition to new partition), the old partition will be renamed.

Example.
Suppose we have a BY RANGE-partitioned table "test" (indexed by 
partitioning key) with a single partition "test_default", which we want 
to split into two partitions ("test_1" and "test_default"), and all 
records should be moved to the "test_1" partition.
When executing the script below, the "test_default" partition will be 
renamed to "test_1".

----
CREATE TABLE test(d date, v text) PARTITION BY RANGE (d);
CREATE TABLE test_default PARTITION OF test DEFAULT;

CREATE INDEX idx_test_d ON test USING btree (d);

INSERT INTO test (d, v)
  SELECT d, 'value_' || md5(random()::text) FROM
   generate_series('2024-01-01', '2024-01-25', interval '10 seconds')
    AS d;

-- Oid of table 'test_default':
SELECT 'test_default'::regclass::oid AS previous_partition_oid;

ALTER TABLE test SPLIT PARTITION test_default INTO
   (PARTITION test_1 FOR VALUES FROM ('2024-01-01') TO ('2024-02-01'),
    PARTITION test_default DEFAULT);

-- Oid of table 'test_1' (should be the same as "previous_partition_oid"):
SELECT 'test_1'::regclass::oid AS current_partition_oid;

DROP TABLE test CASCADE;

-- 
With best regards,
Dmitry Koval

From 88f441946c20b93b216261a8856d837eb8920a89 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 16:06:03 +0300
Subject: [PATCH v21 1/4] ALTER TABLE MERGE PARTITIONS command

---

index 7206da7c53..398040f6e0 100644

 /* ----------------------------------------------------------------
  *		DefineRelation
@@ -4676,6 +4678,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
+			case AT_MergePartitions:
+				cmd_lockmode = AccessExclusiveLock;
+				break;
+
 			default:			/* oops */
 				elog(ERROR, "unrecognized alter table type: %d",
 					 (int) cmd->subtype);
@@ -5090,6 +5096,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			/* No command-specific prep needed */
 			pass = AT_PASS_MISC;
 			break;
+		case AT_MergePartitions:
+			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
+			/* No command-specific prep needed */
+			pass = AT_PASS_MISC;
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -5478,6 +5489,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
 		case AT_DetachPartitionFinalize:
 			address = ATExecDetachPartitionFinalize(rel, ((PartitionCmd *) cmd->def)->name);
 			break;
+		case AT_MergePartitions:
+			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
+									  cur_pass, context);
+			Assert(cmd != NULL);
+			Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
+			ATExecMergePartitions(wqueue, tab, rel, (PartitionCmd *) cmd->def,
+								  context);
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -6464,6 +6483,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
 			return "DETACH PARTITION";
 		case AT_DetachPartitionFinalize:
 			return "DETACH PARTITION ... FINALIZE";
+		case AT_MergePartitions:
+			return "MERGE PARTITIONS";
 		case AT_AddIdentity:
 			return "ALTER COLUMN ... ADD IDENTITY";
 		case AT_SetIdentity:
@@ -18491,6 +18512,37 @@ QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
 	}
 }
 
+/*
@@ -18683,23 +18735,8 @@ ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd,

 	/*
 	 * Generate partition constraint from the partition bound specification.
@@ -20241,3 +20278,283 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 
 	return cstorage;
 }
+
+/*
index d631ac89a9..fe6c43975c 100644
 
@@ -2298,6 +2298,7 @@ partition_cmd:
 
@@ -2312,6 +2313,7 @@ partition_cmd:
 					n->subtype = AT_DetachPartition;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
 					cmd->concurrent = $4;
 					n->def = (Node *) cmd;
 
@@ -2325,6 +2327,21 @@ partition_cmd:
@@ -2341,6 +2358,7 @@ index_partition_cmd:
 
@@ -17284,6 +17302,7 @@ unreserved_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLANS
@@ -17885,6 +17904,7 @@ bare_label_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLACING

+/*

 				/*

+/*

 
index d659adbfd6..5d6893679d 100644
@@ -2568,6 +2568,7 @@ SimpleStats
 SimpleStringList
 SimpleStringListCell
 SingleBoundSortItem
+SinglePartitionSpec
 Size
 SkipPages
 SlabBlock
-- 
2.40.1.windows.1

From ac77b513a2cd18883da84277d76dd29cb165e6d8 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 17:58:52 +0300
Subject: [PATCH v21 2/4] ALTER TABLE SPLIT PARTITION command

---

index 398040f6e0..fbe8b7ccdd 100644

@@ -4678,6 +4681,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
@@ -5096,6 +5103,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
@@ -5489,6 +5501,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
@@ -6483,6 +6503,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
@@ -20279,6 +20301,255 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 	return cstorage;
 }
 
+/*
@@ -20333,6 +20604,142 @@ createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
 				   NULL);
 }
 
+/*
index fe6c43975c..a39f2edbca 100644

@@ -2288,6 +2291,23 @@ alter_table_cmds:
 			| alter_table_cmds ',' alter_table_cmd	{ $$ = lappend($1, $3); }
 		;
 
+partitions_list:
@@ -2332,6 +2352,20 @@ partition_cmd:
@@ -17367,6 +17401,7 @@ unreserved_keyword:
@@ -17981,6 +18016,7 @@ bare_label_keyword:

+/*

 
 /*
  * transformPartitionCmd

 
+/*
 
+/*
 
 	return buf->data;
 }
+
+/*

 

From bc2b618d9445c8d8e84766e625e98e75c1d4d12c Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Tue, 28 Mar 2023 10:50:19 +0300
Subject: [PATCH v21 3/4] Documentation for ALTER TABLE SPLIT PARTITION/MERGE
 PARTITIONS commands

---

index e1d207bc60..0bb5d2c116 100644

 
 
   <para>
 
+  <para>
 
  <refsect1>
-- 
2.40.1.windows.1

From 6742a2532bde1a0fd710aeffc1c4015a4df5f400 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Thu, 26 Oct 2023 03:35:24 +0300
Subject: [PATCH v21 4/4] SPLIT PARTITION optimization

---
 src/backend/commands/tablecmds.c              | 686 +++++++++++++-----
 src/test/regress/expected/partition_split.out | 307 ++++++++
 src/test/regress/sql/partition_split.sql      | 152 ++++
 3 files changed, 978 insertions(+), 167 deletions(-)

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index fbe8b7ccdd..d3f907f119 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -20311,20 +20311,47 @@ typedef struct SplitPartitionContext
 	BulkInsertState bistate;	/* state of bulk inserts for partition */
 	TupleTableSlot *dstslot;	/* slot for insert row into partition */
 	Relation	partRel;		/* relation for partition */
+	SinglePartitionSpec *sps;	/* info about single partition (from SQL
+								 * command) */
 }			SplitPartitionContext;
 
+/*
+ * Struct with context of SPLIT PARTITION operation
+ */
+typedef struct SplitInfo
+{
+	PartitionCmd *cmd;			/* SPLIT PARTITION command info */
+
+	Relation	rel;			/* partitioned table */
+	Relation	splitRel;		/* split partition */
+
+	Oid			defaultPartOid; /* identifier of DEFAULT-partition in rel (if
+								 * exists) */
+	List	   *partContexts;	/* list of structs SplitPartitionContext (each
+								 * struct for each new partition) */
+	SplitPartitionContext *defaultPartCtx;	/* pointer to DEFAULT-partition in
+											 * partContexts list (if exists) */
+	EState	   *estate;			/* working state */
+}			SplitInfo;
 
 /*
- * createSplitPartitionContext: create context for partition and fill it
+ * createSplitPartitionContext: create context for partition
  */
 static SplitPartitionContext *
-createSplitPartitionContext(Relation partRel)
+createSplitPartitionContext(SinglePartitionSpec * sps)
 {
-	SplitPartitionContext *pc;
+	SplitPartitionContext *pc = (SplitPartitionContext *) palloc0(sizeof(SplitPartitionContext));
 
-	pc = (SplitPartitionContext *) palloc0(sizeof(SplitPartitionContext));
-	pc->partRel = partRel;
+	pc->sps = sps;
+	return pc;
+}
 
+/*
+ * fillSplitPartitionContext: fill partition context
+ */
+static void
+fillSplitPartitionContext(SplitPartitionContext * pc)
+{
 	/*
 	 * Prepare a BulkInsertState for table_tuple_insert. The FSM is empty, so
 	 * don't bother using it.
@@ -20335,67 +20362,66 @@ createSplitPartitionContext(Relation partRel)
 	pc->dstslot = MakeSingleTupleTableSlot(RelationGetDescr(pc->partRel),
 										   table_slot_callbacks(pc->partRel));
 	ExecStoreAllNullTuple(pc->dstslot);
-
-	return pc;
 }
 
 /*
  * deleteSplitPartitionContext: delete context for partition
  */
 static void
-deleteSplitPartitionContext(SplitPartitionContext * pc, int ti_options)
+deleteSplitPartitionContext(SplitPartitionContext * pc)
 {
-	ExecDropSingleTupleTableSlot(pc->dstslot);
-	FreeBulkInsertState(pc->bistate);
+	if (pc->dstslot)
+		ExecDropSingleTupleTableSlot(pc->dstslot);
+
+	if (pc->bistate)
+	{
+		/* The FSM is empty, so don't bother using it. */
+		int			ti_options = TABLE_INSERT_SKIP_FSM;
 
-	table_finish_bulk_insert(pc->partRel, ti_options);
+		FreeBulkInsertState(pc->bistate);
+		table_finish_bulk_insert(pc->partRel, ti_options);
+	}
 
 	pfree(pc);
 }
 
 /*
- * moveSplitTableRows: scan split partition (splitRel) of partitioned table
- * (rel) and move rows into new partitions.
+ * createSplitInfo: create SPLIT PARTITION command context, contexts for new
+ *					partitions and generate constraints for them.
+ *					We need to use constraints for optimization.
  *
- * New partitions description:
- * partlist: list of pointers to SinglePartitionSpec structures.
- * newPartRels: list of Relation's.
+ * cmd: SPLIT PARTITION command info.
+ * rel: partitioned table.
+ * splitRel: split partition.
  * defaultPartOid: oid of DEFAULT partition, for table rel.
  */
-static void
-moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPartRels, Oid defaultPartOid)
+static SplitInfo *
+createSplitInfo(PartitionCmd *cmd, Relation rel, Relation splitRel,
+				Oid defaultPartOid)
 {
-	/* The FSM is empty, so don't bother using it. */
-	int			ti_options = TABLE_INSERT_SKIP_FSM;
-	CommandId	mycid;
-	EState	   *estate;
-	ListCell   *listptr,
-			   *listptr2;
-	TupleTableSlot *srcslot;
-	ExprContext *econtext;
-	TableScanDesc scan;
-	Snapshot	snapshot;
-	MemoryContext oldCxt;
 	List	   *partContexts = NIL;
-	TupleConversionMap *tuple_map;
-	SplitPartitionContext *defaultPartCtx = NULL,
-			   *pc;
-	bool		isOldDefaultPart = false;
+	SplitInfo  *si;
+	ListCell   *listptr;
 
-	mycid = GetCurrentCommandId(true);
+	si = (SplitInfo *) palloc0(sizeof(SplitInfo));
 
-	estate = CreateExecutorState();
+	si->cmd = cmd;
+	si->rel = rel;
+	si->splitRel = splitRel;
 
-	forboth(listptr, partlist, listptr2, newPartRels)
+	si->defaultPartOid = defaultPartOid;
+	si->estate = CreateExecutorState();
+
+	/* Create context for each new partition and fill it. */
+	foreach(listptr, cmd->partlist)
 	{
 		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
-
-		pc = createSplitPartitionContext((Relation) lfirst(listptr2));
+		SplitPartitionContext *pc = createSplitPartitionContext(sps);
 
 		if (sps->bound->is_default)
 		{
 			/* We should not create constraint for detached DEFAULT partition. */
-			defaultPartCtx = pc;
+			si->defaultPartCtx = pc;
 		}
 		else
 		{
@@ -20403,9 +20429,8 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 
 			/* Build expression execution states for partition check quals. */
 			partConstraint = get_qual_from_partbound(rel, sps->bound);
-			partConstraint =
-				(List *) eval_const_expressions(NULL,
-												(Node *) partConstraint);
+			partConstraint = (List *) eval_const_expressions(NULL, (Node *) partConstraint);
+
 			/* Make boolean expression for ExecCheck(). */
 			partConstraint = list_make1(make_ands_explicit(partConstraint));
 
@@ -20413,11 +20438,10 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 			 * Map the vars in the constraint expression from rel's attnos to
 			 * splitRel's.
 			 */
-			partConstraint = map_partition_varattnos(partConstraint,
-													 1, splitRel, rel);
+			partConstraint = map_partition_varattnos(partConstraint, 1, splitRel, rel);
 
 			pc->partqualstate =
-				ExecPrepareExpr((Expr *) linitial(partConstraint), estate);
+				ExecPrepareExpr((Expr *) linitial(partConstraint), si->estate);
 			Assert(pc->partqualstate != NULL);
 		}
 
@@ -20425,41 +20449,261 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 		partContexts = lappend(partContexts, pc);
 	}
 
+	si->partContexts = partContexts;
+
+	return si;
+}
+
+/*
+ * deleteSplitInfo: delete SPLIT PARTITION command context
+ */
+static void
+deleteSplitInfo(SplitInfo * si)
+{
+	ListCell   *listptr;
+
+	FreeExecutorState(si->estate);
+
+	foreach(listptr, si->partContexts)
+		deleteSplitPartitionContext((SplitPartitionContext *) lfirst(listptr));
+
+	pfree(si);
+}
+
+/*
+ * checkNewPartitions: simple check of the new partitions.
+ *
+ * cmd: SPLIT PARTITION command info.
+ * splitRelOid: split partition Oid.
+ *
+ * Returns true if one of the new partitions has the same name as the split
+ * partition.
+ */
+static bool
+checkNewPartitions(PartitionCmd *cmd, Oid splitRelOid)
+{
+	Oid			namespaceId;
+	ListCell   *listptr;
+	bool		isSameName = false;
+	char		relname[NAMEDATALEN];
+
+	foreach(listptr, cmd->partlist)
+	{
+		Oid			existing_relid;
+		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
+
+		strlcpy(relname, sps->name->relname, NAMEDATALEN);
+
+		/*
+		 * Look up the namespace in which we are supposed to create the
+		 * partition, check we have permission to create there, lock it
+		 * against concurrent drop, and mark stmt->relation as
+		 * RELPERSISTENCE_TEMP if a temporary namespace is selected.
+		 */
+		namespaceId =
+			RangeVarGetAndCheckCreationNamespace(sps->name, NoLock, NULL);
+
+		/*
+		 * This would fail later on anyway, if the relation already exists.
+		 * But by catching it here we can emit a nicer error message.
+		 */
+		existing_relid = get_relname_relid(relname, namespaceId);
+		if (existing_relid == splitRelOid && !isSameName)
+			/* One new partition can have the same name as split partition. */
+			isSameName = true;
+		else if (existing_relid != InvalidOid)
+			ereport(ERROR,
+					(errcode(ERRCODE_DUPLICATE_TABLE),
+					 errmsg("relation \"%s\" already exists", relname)));
+	}
+
+	return isSameName;
+}
+
+/*
+ * createPartitionTable: create table for new partition with given name
+ * (newPartName) like table (modelRelName)
+ *
+ * Emulates command: CREATE TABLE <newPartName> (LIKE <modelRelName>
+ * INCLUDING ALL EXCLUDING INDEXES)
+ */
+static void
+createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
+					 AlterTableUtilityContext *context)
+{
+	CreateStmt *createStmt;
+	TableLikeClause *tlc;
+	PlannedStmt *wrapper;
+
+	createStmt = makeNode(CreateStmt);
+	createStmt->relation = newPartName;
+	createStmt->tableElts = NIL;
+	createStmt->inhRelations = NIL;
+	createStmt->constraints = NIL;
+	createStmt->options = NIL;
+	createStmt->oncommit = ONCOMMIT_NOOP;
+	createStmt->tablespacename = NULL;
+	createStmt->if_not_exists = false;
+
+	tlc = makeNode(TableLikeClause);
+	tlc->relation = modelRelName;
+
+	/*
+	 * Indexes will be inherited on "attach new partitions" stage, after data
+	 * moving.
+	 */
+	tlc->options = CREATE_TABLE_LIKE_ALL & ~CREATE_TABLE_LIKE_INDEXES;
+	tlc->relationOid = InvalidOid;
+	createStmt->tableElts = lappend(createStmt->tableElts, tlc);
+
+	/* Need to make a wrapper PlannedStmt. */
+	wrapper = makeNode(PlannedStmt);
+	wrapper->commandType = CMD_UTILITY;
+	wrapper->canSetTag = false;
+	wrapper->utilityStmt = (Node *) createStmt;
+	wrapper->stmt_location = context->pstmt->stmt_location;
+	wrapper->stmt_len = context->pstmt->stmt_len;
+
+	ProcessUtility(wrapper,
+				   context->queryString,
+				   false,
+				   PROCESS_UTILITY_SUBCOMMAND,
+				   NULL,
+				   NULL,
+				   None_Receiver,
+				   NULL);
+}
+
+/*
+ * createNewPartitions: simple check of the new partitions.
+ *
+ * si: SPLIT PARTITION command context.
+ * splitName: split partition name.
+ * pcWithAllRows: context of partition that contains all the rows of the split
+ * 				  partition or NULL if no such partition exists.
+ *
+ * Function returns name of split partition (and can change it in case of
+ * optimization with split partition renaming).
+ */
+static RangeVar *
+createNewPartitions(SplitInfo * si, RangeVar *splitName,
+					SplitPartitionContext * pcWithAllRows,
+					AlterTableUtilityContext *context)
+{
+	ListCell   *listptr;
+	Oid			splitRelOid;
+	RangeVar   *splitPartName = splitName;
+
+	splitRelOid = RelationGetRelid(si->splitRel);
+
+	foreach(listptr, si->partContexts)
+	{
+		SplitPartitionContext *pc = (SplitPartitionContext *) lfirst(listptr);
+
+		if (pc == pcWithAllRows)
+		{
+			/* Need to reuse splitRel for partition instead of creation. */
+
+			/*
+			 * We must bump the command counter to make the split partition
+			 * tuple visible for rename.
+			 */
+			CommandCounterIncrement();
+
+			/*
+			 * Rename split partition to new partition.
+			 */
+			RenameRelationInternal(splitRelOid, pc->sps->name->relname, false, false);
+			splitPartName = makeRangeVar(get_namespace_name(RelationGetNamespace(si->splitRel)),
+										 pc->sps->name->relname, -1);
+
+			/*
+			 * We must bump the command counter to make the split partition
+			 * tuple visible after rename.
+			 */
+			CommandCounterIncrement();
+
+			pc->partRel = si->splitRel;
+			/* No need to open relation : splitRel is already opened. */
+		}
+		else
+		{
+			createPartitionTable(pc->sps->name, splitPartName, context);
+
+			/* Open the new partition and acquire exclusive lock on it. */
+			pc->partRel = table_openrv(pc->sps->name, AccessExclusiveLock);
+		}
+	}
+
+	return splitPartName;
+}
+
+/*
+ * moveSplitTableRows: scan split partition (splitRel) of partitioned table
+ * (rel) and move rows into new partitions.
+ *
+ * si: SPLIT PARTITION command context.
+ */
+static void
+moveSplitTableRows(SplitInfo * si)
+{
+	/* The FSM is empty, so don't bother using it. */
+	int			ti_options = TABLE_INSERT_SKIP_FSM;
+	CommandId	mycid;
+	ListCell   *listptr;
+	TupleTableSlot *srcslot;
+	ExprContext *econtext;
+	TableScanDesc scan;
+	Snapshot	snapshot;
+	MemoryContext oldCxt;
+	TupleConversionMap *tuple_map;
+	SplitPartitionContext *pc = NULL;
+	bool		isOldDefaultPart = false;
+	SplitPartitionContext *defaultPartCtx = si->defaultPartCtx;
+
+	mycid = GetCurrentCommandId(true);
+
+	/* Prepare new partitions contexts for insert rows. */
+	foreach(listptr, si->partContexts)
+		fillSplitPartitionContext((SplitPartitionContext *) lfirst(listptr));
+
 	/*
 	 * Create partition context for DEFAULT partition. We can insert values
 	 * into this partition in case spaces with values between new partitions.
 	 */
-	if (!defaultPartCtx && OidIsValid(defaultPartOid))
+	if (!defaultPartCtx && OidIsValid(si->defaultPartOid))
 	{
 		/* Indicate that we allocate context for old DEFAULT partition */
 		isOldDefaultPart = true;
-		defaultPartCtx = createSplitPartitionContext(table_open(defaultPartOid, AccessExclusiveLock));
+		defaultPartCtx = createSplitPartitionContext(NULL);
+		defaultPartCtx->partRel = table_open(si->defaultPartOid, AccessExclusiveLock);
+		fillSplitPartitionContext(defaultPartCtx);
 	}
 
-	econtext = GetPerTupleExprContext(estate);
+	econtext = GetPerTupleExprContext(si->estate);
 
 	/* Create necessary tuple slot. */
-	srcslot = MakeSingleTupleTableSlot(RelationGetDescr(splitRel),
-									   table_slot_callbacks(splitRel));
+	srcslot = MakeSingleTupleTableSlot(RelationGetDescr(si->splitRel),
+									   table_slot_callbacks(si->splitRel));
 
 	/*
 	 * Map computing for moving attributes of split partition to new partition
 	 * (for first new partition but other new partitions can use the same
 	 * map).
 	 */
-	pc = (SplitPartitionContext *) lfirst(list_head(partContexts));
-	tuple_map = convert_tuples_by_name(RelationGetDescr(splitRel),
+	pc = (SplitPartitionContext *) lfirst(list_head(si->partContexts));
+	tuple_map = convert_tuples_by_name(RelationGetDescr(si->splitRel),
 									   RelationGetDescr(pc->partRel));
 
 	/* Scan through the rows. */
 	snapshot = RegisterSnapshot(GetLatestSnapshot());
-	scan = table_beginscan(splitRel, snapshot, 0, NULL);
+	scan = table_beginscan(si->splitRel, snapshot, 0, NULL);
 
 	/*
 	 * Switch to per-tuple memory context and reset it for each tuple
 	 * produced, so we don't leak memory.
 	 */
-	oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
+	oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(si->estate));
 
 	while (table_scan_getnextslot(scan, ForwardScanDirection, srcslot))
 	{
@@ -20472,7 +20716,7 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 		econtext->ecxt_scantuple = srcslot;
 
 		/* Search partition for current slot srcslot. */
-		foreach(listptr, partContexts)
+		foreach(listptr, si->partContexts)
 		{
 			pc = (SplitPartitionContext *) lfirst(listptr);
 
@@ -20493,7 +20737,7 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 				ereport(ERROR,
 						(errcode(ERRCODE_CHECK_VIOLATION),
 						 errmsg("can not find partition for split partition row"),
-						 errtable(splitRel)));
+						 errtable(si->splitRel)));
 		}
 
 		if (tuple_map)
@@ -20534,74 +20778,208 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 
 	ExecDropSingleTupleTableSlot(srcslot);
 
-	FreeExecutorState(estate);
-
-	foreach(listptr, partContexts)
-		deleteSplitPartitionContext((SplitPartitionContext *) lfirst(listptr), ti_options);
-
 	/* Need to close table and free buffers for DEFAULT partition. */
 	if (isOldDefaultPart)
 	{
-		Relation defaultPartRel = defaultPartCtx->partRel;
+		Relation	defaultPartRel = defaultPartCtx->partRel;
 
-		deleteSplitPartitionContext(defaultPartCtx, ti_options);
+		deleteSplitPartitionContext(defaultPartCtx);
 		/* Keep the lock until commit. */
 		table_close(defaultPartRel, NoLock);
 	}
 }
 
 /*
- * createPartitionTable: create table for new partition with given name
- * (newPartName) like table (modelRelName)
+ * findNewPartForSlot: find partition that contains slot value.
  *
- * Emulates command: CREATE TABLE <newPartName> (LIKE <modelRelName>
- * INCLUDING ALL EXCLUDING INDEXES)
+ * si: SPLIT PARTITION context.
+ * checkPc: partition context for check slot value (can be NULL).
+ * slot: value to check.
  */
-static void
-createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
-					 AlterTableUtilityContext *context)
+static SplitPartitionContext *
+findNewPartForSlot(SplitInfo * si, SplitPartitionContext * checkPc, TupleTableSlot *slot)
 {
-	CreateStmt *createStmt;
-	TableLikeClause *tlc;
-	PlannedStmt *wrapper;
+	ListCell   *listptr;
+	ExprContext *econtext;
+	MemoryContext oldCxt;
+	SplitPartitionContext *result = NULL;
 
-	createStmt = makeNode(CreateStmt);
-	createStmt->relation = newPartName;
-	createStmt->tableElts = NIL;
-	createStmt->inhRelations = NIL;
-	createStmt->constraints = NIL;
-	createStmt->options = NIL;
-	createStmt->oncommit = ONCOMMIT_NOOP;
-	createStmt->tablespacename = NULL;
-	createStmt->if_not_exists = false;
+	econtext = GetPerTupleExprContext(si->estate);
 
-	tlc = makeNode(TableLikeClause);
-	tlc->relation = modelRelName;
+	/* Make sure the tuple is fully deconstructed. */
+	slot_getallattrs(slot);
+
+	econtext->ecxt_scantuple = slot;
 
 	/*
-	 * Indexes will be inherited on "attach new partitions" stage, after data
-	 * moving.
+	 * Switch to per-tuple memory context and reset it after each check, so we
+	 * don't leak memory.
 	 */
-	tlc->options = CREATE_TABLE_LIKE_ALL & ~CREATE_TABLE_LIKE_INDEXES;
-	tlc->relationOid = InvalidOid;
-	createStmt->tableElts = lappend(createStmt->tableElts, tlc);
+	oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(si->estate));
 
-	/* Need to make a wrapper PlannedStmt. */
-	wrapper = makeNode(PlannedStmt);
-	wrapper->commandType = CMD_UTILITY;
-	wrapper->canSetTag = false;
-	wrapper->utilityStmt = (Node *) createStmt;
-	wrapper->stmt_location = context->pstmt->stmt_location;
-	wrapper->stmt_len = context->pstmt->stmt_len;
+	if (checkPc)
+	{
+		if (ExecCheck(checkPc->partqualstate, econtext))
+		{
+			ResetExprContext(econtext);
+			result = checkPc;
+		}
+	}
+	else
+	{
+		/* Search partition for current slot srcslot. */
+		foreach(listptr, si->partContexts)
+		{
+			SplitPartitionContext *pc = (SplitPartitionContext *) lfirst(listptr);
 
-	ProcessUtility(wrapper,
-				   context->queryString,
-				   false,
-				   PROCESS_UTILITY_SUBCOMMAND,
-				   NULL,
-				   NULL,
-				   None_Receiver,
-				   NULL);
+			if (pc->partqualstate /* skip DEFAULT partition */ &&
+				ExecCheck(pc->partqualstate, econtext))
+			{
+				ResetExprContext(econtext);
+				result = pc;
+				break;
+			}
+			ResetExprContext(econtext);
+		}
+
+		/* We not found partition with borders but exists DEFAULT partition. */
+		if (!result && si->defaultPartCtx)
+			result = si->defaultPartCtx;
+
+		/*
+		 * "result" can be NULL here because can be spaces between of the new
+		 * partitions and rows from the spaces can be moved to the DEFAULT
+		 * partition of the partitioned table.
+		 */
+	}
+
+	MemoryContextSwitchTo(oldCxt);
+
+	return result;
+}
+
+/*
+ * findNewPartWithAllRows: find partition that contains all the rows of the
+ * split partition; returns partition context if partition was found.
+ *
+ * si: SPLIT PARTITION context.
+ */
+static SplitPartitionContext *
+findNewPartWithAllRows(SplitInfo * si)
+{
+	PartitionKey key = RelationGetPartitionKey(si->rel);
+	ListCell   *index;
+	int			partnatts;
+	SplitPartitionContext *result = NULL;
+	AttrMap    *map;
+	AttrNumber *partattrs;
+	int			i;
+
+	/* We can use optimization for BY RANGE partitioning only. */
+	if (key->strategy != PARTITION_STRATEGY_RANGE)
+		return NULL;
+
+	partnatts = get_partition_natts(key);
+
+	/*
+	 * Partition key contains columns of partitioned tables si->rel but index
+	 * contains columns of si->splitRel. So we need a map for convert
+	 * attributes numbers (si->rel) -> (si->splitRel).
+	 */
+	map = build_attrmap_by_name_if_req(RelationGetDescr(si->splitRel),
+									   RelationGetDescr(si->rel),
+									   false);
+	if (map)
+	{
+		/*
+		 * Columns order in a partitioned table and split partition is
+		 * different. So need to create a new array with attribute numbers.
+		 */
+		partattrs = palloc(sizeof(AttrNumber) * partnatts);
+		for (i = 0; i < partnatts; i++)
+		{
+			AttrNumber	attr_num = get_partition_col_attnum(key, i);
+
+			partattrs[i] = map->attnums[attr_num - 1];
+		}
+	}
+	else
+	{
+		/* We can use array of partition key. */
+		partattrs = key->partattrs;
+	}
+
+	/* Scan all indexes of split partition. */
+	foreach(index, RelationGetIndexList(si->splitRel))
+	{
+		Oid			thisIndexOid = lfirst_oid(index);
+		Relation	indexRel = index_open(thisIndexOid, AccessShareLock);
+
+		/*
+		 * Index should be valid, btree (for searching min/max) and contain
+		 * the same columns as partition key.
+		 */
+		if (indexRel->rd_index->indisvalid &&
+			indexRel->rd_rel->relam == BTREE_AM_OID &&
+			indexRel->rd_index->indnatts == partnatts)
+		{
+			for (i = 0; i < indexRel->rd_index->indnatts; i++)
+			{
+				if (indexRel->rd_index->indkey.values[i] != partattrs[i])
+					break;
+			}
+
+			/* Index found? */
+			if (i == indexRel->rd_index->indnatts)
+			{
+				IndexScanDesc indexScan;
+				TupleTableSlot *slot;
+
+				indexScan = index_beginscan(si->splitRel, indexRel, SnapshotAny, 0, 0);
+				do
+				{
+					SplitPartitionContext *pc;
+
+					/* Search a minimum index value. */
+					index_rescan(indexScan, NULL, 0, NULL, 0);
+					slot = table_slot_create(si->splitRel, NULL);
+					if (!index_getnext_slot(indexScan, ForwardScanDirection, slot))
+					{
+						ExecDropSingleTupleTableSlot(slot);
+						break;
+					}
+					/* Find partition context for minimum index value. */
+					pc = findNewPartForSlot(si, NULL, slot);
+					ExecDropSingleTupleTableSlot(slot);
+
+					/* Search a maximum index value. */
+					index_rescan(indexScan, NULL, 0, NULL, 0);
+					slot = table_slot_create(si->splitRel, NULL);
+					if (!index_getnext_slot(indexScan, BackwardScanDirection, slot))
+					{
+						ExecDropSingleTupleTableSlot(slot);
+						break;
+					}
+					/* Check partition context "pc" for maximum index value. */
+					result = findNewPartForSlot(si, pc, slot);
+					ExecDropSingleTupleTableSlot(slot);
+				} while (0);
+
+				index_endscan(indexScan);
+				index_close(indexRel, AccessShareLock);
+				goto done;
+			}
+		}
+		index_close(indexRel, AccessShareLock);
+	}
+
+done:
+	if (map)
+	{
+		pfree(partattrs);
+		free_attrmap(map);
+	}
+	return result;
 }
 
 /*
@@ -20613,16 +20991,14 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 {
 	Relation	splitRel;
 	Oid			splitRelOid;
-	char		relname[NAMEDATALEN];
-	Oid			namespaceId;
-	ListCell   *listptr,
-			   *listptr2;
+	ListCell   *listptr;
 	bool		isSameName = false;
 	char		tmpRelName[NAMEDATALEN];
-	List	   *newPartRels = NIL;
 	ObjectAddress object;
 	RangeVar   *splitPartName = cmd->name;
 	Oid			defaultPartOid;
+	SplitPartitionContext *pcWithAllRows;
+	SplitInfo  *si;
 
 	defaultPartOid = get_default_oid_from_partdesc(RelationGetPartitionDesc(rel, true));
 
@@ -20641,35 +21017,7 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 	splitRelOid = RelationGetRelid(splitRel);
 
 	/* Check descriptions of new partitions. */
-	foreach(listptr, cmd->partlist)
-	{
-		Oid			existing_relid;
-		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
-
-		strlcpy(relname, sps->name->relname, NAMEDATALEN);
-
-		/*
-		 * Look up the namespace in which we are supposed to create the
-		 * partition, check we have permission to create there, lock it
-		 * against concurrent drop, and mark stmt->relation as
-		 * RELPERSISTENCE_TEMP if a temporary namespace is selected.
-		 */
-		namespaceId =
-			RangeVarGetAndCheckCreationNamespace(sps->name, NoLock, NULL);
-
-		/*
-		 * This would fail later on anyway, if the relation already exists.
-		 * But by catching it here we can emit a nicer error message.
-		 */
-		existing_relid = get_relname_relid(relname, namespaceId);
-		if (existing_relid == splitRelOid && !isSameName)
-			/* One new partition can have the same name as split partition. */
-			isSameName = true;
-		else if (existing_relid != InvalidOid)
-			ereport(ERROR,
-					(errcode(ERRCODE_DUPLICATE_TABLE),
-					 errmsg("relation \"%s\" already exists", relname)));
-	}
+	isSameName = checkNewPartitions(cmd, splitRelOid);
 
 	/* Detach split partition. */
 	RemoveInheritance(splitRel, rel, false);
@@ -20690,8 +21038,7 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 		/* Rename partition. */
 		sprintf(tmpRelName, "split-%u-%X-tmp", RelationGetRelid(rel), MyProcPid);
 		RenameRelationInternal(splitRelOid, tmpRelName, false, false);
-		splitPartName = makeRangeVar(
-									 get_namespace_name(RelationGetNamespace(splitRel)),
+		splitPartName = makeRangeVar(get_namespace_name(RelationGetNamespace(splitRel)),
 									 tmpRelName, -1);
 
 		/*
@@ -20701,43 +21048,48 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 		CommandCounterIncrement();
 	}
 
-	/* Create new partitions (like split partition), without indexes. */
-	foreach(listptr, cmd->partlist)
-	{
-		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
-		Relation	newPartRel;
+	/* Create SPLIT PARTITION context. */
+	si = createSplitInfo(cmd, rel, splitRel, defaultPartOid);
 
-		createPartitionTable(sps->name, splitPartName, context);
+	/*
+	 * Optimization: if exist a new partition that contains all the rows of
+	 * the split partition then do not copy rows, rename the split partition.
+	 */
+	pcWithAllRows = findNewPartWithAllRows(si);
 
-		/* Open the new partition and acquire exclusive lock on it. */
-		newPartRel = table_openrv(sps->name, AccessExclusiveLock);
+	/* Create new partitions (like split partition), without indexes. */
+	splitPartName = createNewPartitions(si, splitPartName, pcWithAllRows, context);
 
-		newPartRels = lappend(newPartRels, newPartRel);
+	if (!pcWithAllRows)
+	{
+		/* Copy data from split partition to new partitions. */
+		moveSplitTableRows(si);
+		/* Keep the lock until commit. */
+		table_close(splitRel, NoLock);
 	}
 
-	/* Copy data from split partition to new partitions. */
-	moveSplitTableRows(rel, splitRel, cmd->partlist, newPartRels, defaultPartOid);
-	/* Keep the lock until commit. */
-	table_close(splitRel, NoLock);
-
 	/* Attach new partitions to partitioned table. */
-	forboth(listptr, cmd->partlist, listptr2, newPartRels)
+	foreach(listptr, si->partContexts)
 	{
-		SinglePartitionSpec *sps = (SinglePartitionSpec *) lfirst(listptr);
-		Relation	newPartRel = (Relation) lfirst(listptr2);
+		SplitPartitionContext *pc = (SplitPartitionContext *) lfirst(listptr);
 
 		/* wqueue = NULL: verification for each cloned constraint is not need. */
-		attachPartitionTable(NULL, rel, newPartRel, sps->bound);
+		attachPartitionTable(NULL, rel, pc->partRel, pc->sps->bound);
 		/* Keep the lock until commit. */
-		table_close(newPartRel, NoLock);
+		table_close(pc->partRel, NoLock);
 	}
 
-	/* Drop split partition. */
-	object.classId = RelationRelationId;
-	object.objectId = splitRelOid;
-	object.objectSubId = 0;
-	/* Probably DROP_CASCADE is not needed. */
-	performDeletion(&object, DROP_RESTRICT, 0);
+	if (!pcWithAllRows)
+	{
+		/* Drop split partition. */
+		object.classId = RelationRelationId;
+		object.objectId = splitRelOid;
+		object.objectSubId = 0;
+		/* Probably DROP_CASCADE is not needed. */
+		performDeletion(&object, DROP_RESTRICT, 0);
+	}
+
+	deleteSplitInfo(si);
 }
 
 /*
@@ -20883,8 +21235,8 @@ ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel,
 							RelationGetRelationName(pc->partRel))));
 
 		/*
-		 * Checking that two partitions have the same name was before,
-		 * in function transformPartitionCmdForMerge().
+		 * Checking that two partitions have the same name was before, in
+		 * function transformPartitionCmdForMerge().
 		 */
 		if (equal(name, cmd->name))
 			/* One new partition can have the same name as merged partition. */
diff --git a/src/test/regress/expected/partition_split.out b/src/test/regress/expected/partition_split.out
index 08bf021796..ece707fdc6 100644
--- a/src/test/regress/expected/partition_split.out
+++ b/src/test/regress/expected/partition_split.out
@@ -1414,4 +1414,311 @@ SELECT * FROM sales_others;
 
 DROP TABLE sales_range;
 --
+--
+-- Tests for SPLIT optimization (BY RANGE partitioning): if one of the new
+-- partitions contains all the rows of the split partition, then we can rename
+-- the split partition instead of creating a new partition and moving the rows.
+--
+-- 1. Optimization should be used.
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+CREATE INDEX idx_test_i ON test(i);
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a15', 15), ('a12', 12), ('a17', 17), ('a11', 11);
+-- should be rows 15, 12, 17, 11:
+SELECT i FROM test_def;
+ i  
+----
+ 15
+ 12
+ 17
+ 11
+(4 rows)
+
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 't' (table "test_2" after SPLIT should be the same as table
+-- "test_def" before SPLIT):
+SELECT 'test_2'::regclass::oid=:prev_oid;
+ ?column? 
+----------
+ t
+(1 row)
+
+-- should be rows 15, 12, 17, 11:
+SELECT i FROM test_2;
+ i  
+----
+ 15
+ 12
+ 17
+ 11
+(4 rows)
+
+-- should be 0 rows:
+SELECT i FROM test_def;
+ i 
+---
+(0 rows)
+
+-- should be 6 rows:
+SELECT * FROM test;
+ name | i  
+------+----
+ a1   |  1
+ a5   |  5
+ a15  | 15
+ a12  | 12
+ a17  | 17
+ a11  | 11
+(6 rows)
+
+DROP TABLE test CASCADE;
+--
+-- 2. Optimization cannot be used because not exists btree-index on the
+-- partition key (it is used to check the placement of rows in the partitions).
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a15', 15), ('a12', 12), ('a17', 17), ('a11', 11);
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 'f' (tables "test_2" and "test_def" should be different):
+SELECT 'test_2'::regclass::oid=:prev_oid;
+ ?column? 
+----------
+ f
+(1 row)
+
+-- should be rows 15, 12, 17, 11:
+SELECT i FROM test_2;
+ i  
+----
+ 15
+ 12
+ 17
+ 11
+(4 rows)
+
+-- should be 6 rows:
+SELECT * FROM test;
+ name | i  
+------+----
+ a1   |  1
+ a5   |  5
+ a15  | 15
+ a12  | 12
+ a17  | 17
+ a11  | 11
+(6 rows)
+
+DROP TABLE test CASCADE;
+--
+-- 3. Optimization cannot be used because rows should be moved into different
+-- partitions.
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+CREATE INDEX idx_test_i ON test(i);
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a15', 15), ('a12', 12), ('a27', 27), ('a11', 11);
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 'f' (tables "test_2" and "test_def" should be different):
+SELECT 'test_2'::regclass::oid=:prev_oid;
+ ?column? 
+----------
+ f
+(1 row)
+
+-- should be rows 15, 12, 11:
+SELECT i FROM test_2;
+ i  
+----
+ 15
+ 12
+ 11
+(3 rows)
+
+-- should be 6 rows:
+SELECT * FROM test;
+ name | i  
+------+----
+ a1   |  1
+ a5   |  5
+ a15  | 15
+ a12  | 12
+ a11  | 11
+ a27  | 27
+(6 rows)
+
+DROP TABLE test CASCADE;
+--
+-- 4. Optimization should be used, DEFAUT partition renames to DEFAULT
+-- partition.
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+CREATE INDEX idx_test_i ON test(i);
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a25', 25), ('a22', 22), ('a27', 27), ('a21', 21);
+-- should be rows 25, 22, 27, 21:
+SELECT i FROM test_def;
+ i  
+----
+ 25
+ 22
+ 27
+ 21
+(4 rows)
+
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 't' (table "test_def" after SPLIT should be the same as table
+-- "test_def" before SPLIT):
+SELECT 'test_def'::regclass::oid=:prev_oid;
+ ?column? 
+----------
+ t
+(1 row)
+
+-- should be 0 rows:
+SELECT i FROM test_2;
+ i 
+---
+(0 rows)
+
+-- should be rows 25, 22, 27, 21:
+SELECT i FROM test_def;
+ i  
+----
+ 25
+ 22
+ 27
+ 21
+(4 rows)
+
+-- should be 6 rows:
+SELECT * FROM test;
+ name | i  
+------+----
+ a1   |  1
+ a5   |  5
+ a25  | 25
+ a22  | 22
+ a27  | 27
+ a21  | 21
+(6 rows)
+
+DROP TABLE test CASCADE;
+--
+-- 5. Optimization should be used, 2-column partition key + different columns
+-- order in partitions.
+--
+CREATE TABLE test_2colkey(s smallint, b bigint, t text) PARTITION BY RANGE (b, s);
+CREATE TABLE test_2colkey_1 PARTITION OF test_2colkey FOR VALUES FROM (1000000001, 1) TO (1000000100, 100);
+CREATE TABLE test_2colkey_def(i int, b bigint, s smallint, t text);
+ALTER TABLE test_2colkey_def DROP COLUMN i;
+ALTER TABLE test_2colkey ATTACH PARTITION test_2colkey_def DEFAULT;
+CREATE INDEX idx_test_2colkey_s_b ON test_2colkey(b, s);
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000010, 3, 'value_10_3');
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000120, 4, 'value_120_4');
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000003, 5, 'value_3_5');
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000124, 2, 'value_124_2');
+-- should be 4 rows:
+SELECT b, s FROM test_2colkey;
+     b      | s 
+------------+---
+ 1000000010 | 3
+ 1000000003 | 5
+ 1000000120 | 4
+ 1000000124 | 2
+(4 rows)
+
+-- should be 2 rows:
+SELECT b, s FROM test_2colkey_def;
+     b      | s 
+------------+---
+ 1000000120 | 4
+ 1000000124 | 2
+(2 rows)
+
+SELECT 'test_2colkey_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test_2colkey SPLIT PARTITION test_2colkey_def INTO
+  (PARTITION test_2colkey_2 FOR VALUES FROM (1000000101, 1) TO (1000000200, 100),
+   PARTITION test_2colkey_def DEFAULT);
+-- should be 't' (table "test_2colkey_2" after SPLIT should be the same as table
+-- "test_2colkey_def" before SPLIT):
+SELECT 'test_2colkey_2'::regclass::oid=:prev_oid;
+ ?column? 
+----------
+ t
+(1 row)
+
+-- should be 2 rows:
+SELECT b, s FROM test_2colkey_2;
+     b      | s 
+------------+---
+ 1000000120 | 4
+ 1000000124 | 2
+(2 rows)
+
+-- should be 0 rows:
+SELECT b, s FROM test_2colkey_def;
+ b | s 
+---+---
+(0 rows)
+
+-- should be 6 rows:
+SELECT b, s FROM test_2colkey;
+     b      | s 
+------------+---
+ 1000000010 | 3
+ 1000000003 | 5
+ 1000000120 | 4
+ 1000000124 | 2
+(4 rows)
+
+--
+-- 5.1. Optimization cannot be used.
+--
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000200, 1, 'value_200_1');
+SELECT 'test_2colkey_2'::regclass::oid AS prev_oid \gset
+ALTER TABLE test_2colkey SPLIT PARTITION test_2colkey_2 INTO
+  (PARTITION test_2colkey_2 FOR VALUES FROM (1000000101, 1) TO (1000000150, 100),
+   PARTITION test_2colkey_3 FOR VALUES FROM (1000000151, 1) TO (1000000200, 100));
+-- should be 'f' (optimization is not used):
+SELECT 'test_2colkey_2'::regclass::oid=:prev_oid;
+ ?column? 
+----------
+ f
+(1 row)
+
+-- should be 2 rows:
+SELECT b, s FROM test_2colkey_2;
+     b      | s 
+------------+---
+ 1000000120 | 4
+ 1000000124 | 2
+(2 rows)
+
+-- should be 1 row:
+SELECT b, s FROM test_2colkey_3;
+     b      | s 
+------------+---
+ 1000000200 | 1
+(1 row)
+
+DROP TABLE test_2colkey CASCADE;
+--
 DROP SCHEMA partition_split_schema;
diff --git a/src/test/regress/sql/partition_split.sql b/src/test/regress/sql/partition_split.sql
index 58e17f33e8..627977ef30 100644
--- a/src/test/regress/sql/partition_split.sql
+++ b/src/test/regress/sql/partition_split.sql
@@ -829,5 +829,157 @@ SELECT * FROM sales_others;
 
 DROP TABLE sales_range;
 
+--
+--
+-- Tests for SPLIT optimization (BY RANGE partitioning): if one of the new
+-- partitions contains all the rows of the split partition, then we can rename
+-- the split partition instead of creating a new partition and moving the rows.
+--
+-- 1. Optimization should be used.
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+CREATE INDEX idx_test_i ON test(i);
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a15', 15), ('a12', 12), ('a17', 17), ('a11', 11);
+-- should be rows 15, 12, 17, 11:
+SELECT i FROM test_def;
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 't' (table "test_2" after SPLIT should be the same as table
+-- "test_def" before SPLIT):
+SELECT 'test_2'::regclass::oid=:prev_oid;
+-- should be rows 15, 12, 17, 11:
+SELECT i FROM test_2;
+-- should be 0 rows:
+SELECT i FROM test_def;
+-- should be 6 rows:
+SELECT * FROM test;
+DROP TABLE test CASCADE;
+--
+-- 2. Optimization cannot be used because not exists btree-index on the
+-- partition key (it is used to check the placement of rows in the partitions).
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a15', 15), ('a12', 12), ('a17', 17), ('a11', 11);
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 'f' (tables "test_2" and "test_def" should be different):
+SELECT 'test_2'::regclass::oid=:prev_oid;
+-- should be rows 15, 12, 17, 11:
+SELECT i FROM test_2;
+-- should be 6 rows:
+SELECT * FROM test;
+DROP TABLE test CASCADE;
+--
+-- 3. Optimization cannot be used because rows should be moved into different
+-- partitions.
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+CREATE INDEX idx_test_i ON test(i);
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a15', 15), ('a12', 12), ('a27', 27), ('a11', 11);
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 'f' (tables "test_2" and "test_def" should be different):
+SELECT 'test_2'::regclass::oid=:prev_oid;
+-- should be rows 15, 12, 11:
+SELECT i FROM test_2;
+-- should be 6 rows:
+SELECT * FROM test;
+DROP TABLE test CASCADE;
+--
+-- 4. Optimization should be used, DEFAUT partition renames to DEFAULT
+-- partition.
+--
+CREATE TABLE test(name text, i int) PARTITION BY RANGE (i);
+CREATE TABLE test_1 PARTITION OF test FOR VALUES FROM (1) TO (10);
+CREATE TABLE test_def PARTITION OF test DEFAULT;
+CREATE INDEX idx_test_i ON test(i);
+INSERT INTO test(name, i) VALUES
+  ('a1', 1), ('a5', 5), ('a25', 25), ('a22', 22), ('a27', 27), ('a21', 21);
+-- should be rows 25, 22, 27, 21:
+SELECT i FROM test_def;
+SELECT 'test_def'::regclass::oid AS prev_oid \gset
+ALTER TABLE test SPLIT PARTITION test_def INTO 
+  (PARTITION test_def DEFAULT, PARTITION test_2 FOR VALUES FROM (11) TO (19));
+-- should be 't' (table "test_def" after SPLIT should be the same as table
+-- "test_def" before SPLIT):
+SELECT 'test_def'::regclass::oid=:prev_oid;
+-- should be 0 rows:
+SELECT i FROM test_2;
+-- should be rows 25, 22, 27, 21:
+SELECT i FROM test_def;
+-- should be 6 rows:
+SELECT * FROM test;
+DROP TABLE test CASCADE;
+--
+-- 5. Optimization should be used, 2-column partition key + different columns
+-- order in partitions.
+--
+CREATE TABLE test_2colkey(s smallint, b bigint, t text) PARTITION BY RANGE (b, s);
+CREATE TABLE test_2colkey_1 PARTITION OF test_2colkey FOR VALUES FROM (1000000001, 1) TO (1000000100, 100);
+CREATE TABLE test_2colkey_def(i int, b bigint, s smallint, t text);
+ALTER TABLE test_2colkey_def DROP COLUMN i;
+ALTER TABLE test_2colkey ATTACH PARTITION test_2colkey_def DEFAULT;
+CREATE INDEX idx_test_2colkey_s_b ON test_2colkey(b, s);
+
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000010, 3, 'value_10_3');
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000120, 4, 'value_120_4');
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000003, 5, 'value_3_5');
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000124, 2, 'value_124_2');
+
+-- should be 4 rows:
+SELECT b, s FROM test_2colkey;
+-- should be 2 rows:
+SELECT b, s FROM test_2colkey_def;
+
+SELECT 'test_2colkey_def'::regclass::oid AS prev_oid \gset
+
+ALTER TABLE test_2colkey SPLIT PARTITION test_2colkey_def INTO
+  (PARTITION test_2colkey_2 FOR VALUES FROM (1000000101, 1) TO (1000000200, 100),
+   PARTITION test_2colkey_def DEFAULT);
+
+-- should be 't' (table "test_2colkey_2" after SPLIT should be the same as table
+-- "test_2colkey_def" before SPLIT):
+SELECT 'test_2colkey_2'::regclass::oid=:prev_oid;
+
+-- should be 2 rows:
+SELECT b, s FROM test_2colkey_2;
+-- should be 0 rows:
+SELECT b, s FROM test_2colkey_def;
+-- should be 6 rows:
+SELECT b, s FROM test_2colkey;
+
+--
+-- 5.1. Optimization cannot be used.
+--
+INSERT INTO test_2colkey (b, s, t) VALUES (1000000200, 1, 'value_200_1');
+
+SELECT 'test_2colkey_2'::regclass::oid AS prev_oid \gset
+
+ALTER TABLE test_2colkey SPLIT PARTITION test_2colkey_2 INTO
+  (PARTITION test_2colkey_2 FOR VALUES FROM (1000000101, 1) TO (1000000150, 100),
+   PARTITION test_2colkey_3 FOR VALUES FROM (1000000151, 1) TO (1000000200, 100));
+
+-- should be 'f' (optimization is not used):
+SELECT 'test_2colkey_2'::regclass::oid=:prev_oid;
+
+-- should be 2 rows:
+SELECT b, s FROM test_2colkey_2;
+-- should be 1 row:
+SELECT b, s FROM test_2colkey_3;
+
+DROP TABLE test_2colkey CASCADE;
+
 --
 DROP SCHEMA partition_split_schema;
-- 
2.40.1.windows.1

---

From: vignesh C <[email-masked]>
Date: Fri, 26 Jan 2024 18:20:07 +0530

> Added commit v21-0004-SPLIT-PARTITION-optimization.patch.

CFBot shows that the patch does not apply anymore as in [1]:
=== Applying patches on top of PostgreSQL commit ID
8ba6fdf905d0f5aef70ced4504c6ad297bfe08ea ===
=== applying patch ./v21-0001-ALTER-TABLE-MERGE-PARTITIONS-command.patch
patching file src/backend/commands/tablecmds.c
...
Hunk #7 FAILED at 18735.
Hunk #8 succeeded at 20608 (offset 315 lines).
1 out of 8 hunks FAILED -- saving rejects to file
src/backend/commands/tablecmds.c.rej
patching file src/backend/parser/gram.y

Please post an updated version for the same.

[1] - http://cfbot.cputube.org/patch_46_3659.log

Regards,
Vignesh

---

From: Alvaro Herrera <[email-masked]>
Date: Fri, 26 Jan 2024 15:01:52 +0100

> Please post an updated version for the same.

Here's a rebase.  I only fixed the conflicts, didn't review.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/

---

From: Alvaro Herrera <[email-masked]>
Date: Fri, 26 Jan 2024 17:36:33 +0100

> Here's a rebase.  I only fixed the conflicts, didn't review.

Hmm, but I got the attached regression.diffs with it.  I didn't
investigate further, but it looks like the recent changes to replication
identity for partitioned tables has broken the regression tests.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/
"This is what I like so much about PostgreSQL.  Most of the surprises
are of the "oh wow!  That's cool" Not the "oh shit!" kind.  :)"
Scott Marlowe, http://archives.postgresql.org/pgsql-admin/2008-10/msg00152.php
diff -U3 /pgsql/source/master/src/test/regress/expected/partition_split.out /home/alvherre/Code/pgsql-build/master/src/test/regress/results/partition_split.out
--- /pgsql/source/master/src/test/regress/expected/partition_split.out	2024-01-26 14:57:39.549730792 +0100
+++ /home/alvherre/Code/pgsql-build/master/src/test/regress/results/partition_split.out	2024-01-26 15:22:15.007059433 +0100
@@ -777,8 +777,12 @@
 -- Create new partition with identity-column:
 CREATE TABLE salesmans2_5(salesman_id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY, salesman_name VARCHAR(30));
 ALTER TABLE salesmans ATTACH PARTITION salesmans2_5 FOR VALUES FROM (2) TO (5);
+ERROR:  table "salesmans2_5" being attached contains an identity column "salesman_id"
+DETAIL:  The new partition may not contain an identity column.
 INSERT INTO salesmans (salesman_name) VALUES ('Poirot');
 INSERT INTO salesmans (salesman_name) VALUES ('Ivanov');
+ERROR:  no partition of relation "salesmans" found for row
+DETAIL:  Partition key of the failing row contains (salesman_id) = (2).
 SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans'::regclass::oid;
     attname    | attidentity | attgenerated 
 ---------------+-------------+--------------
@@ -789,7 +793,7 @@
 SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans1_2'::regclass::oid;
     attname    | attidentity | attgenerated 
 ---------------+-------------+--------------
- salesman_id   |             | 
+ salesman_id   | a           | 
  salesman_name |             | 
 (2 rows)
 
@@ -805,8 +809,13 @@
   (PARTITION salesmans2_3 FOR VALUES FROM (2) TO (3),
    PARTITION salesmans3_4 FOR VALUES FROM (3) TO (4),
    PARTITION salesmans4_5 FOR VALUES FROM (4) TO (5));
+ERROR:  partition bound for relation "salesmans2_5" is null
 INSERT INTO salesmans (salesman_name) VALUES ('May');
+ERROR:  no partition of relation "salesmans" found for row
+DETAIL:  Partition key of the failing row contains (salesman_id) = (3).
 INSERT INTO salesmans (salesman_name) VALUES ('Ford');
+ERROR:  no partition of relation "salesmans" found for row
+DETAIL:  Partition key of the failing row contains (salesman_id) = (4).
 SELECT * FROM salesmans1_2;
  salesman_id | salesman_name 
 -------------+---------------
@@ -814,23 +823,17 @@
 (1 row)
 
 SELECT * FROM salesmans2_3;
- salesman_id | salesman_name 
--------------+---------------
-           2 | Ivanov
-(1 row)
-
+ERROR:  relation "salesmans2_3" does not exist
+LINE 1: SELECT * FROM salesmans2_3;
+                      ^
 SELECT * FROM salesmans3_4;
- salesman_id | salesman_name 
--------------+---------------
-           3 | May
-(1 row)
-
+ERROR:  relation "salesmans3_4" does not exist
+LINE 1: SELECT * FROM salesmans3_4;
+                      ^
 SELECT * FROM salesmans4_5;
- salesman_id | salesman_name 
--------------+---------------
-           4 | Ford
-(1 row)
-
+ERROR:  relation "salesmans4_5" does not exist
+LINE 1: SELECT * FROM salesmans4_5;
+                      ^
 SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans'::regclass::oid;
     attname    | attidentity | attgenerated 
 ---------------+-------------+--------------
@@ -841,32 +844,23 @@
 SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans1_2'::regclass::oid;
     attname    | attidentity | attgenerated 
 ---------------+-------------+--------------
- salesman_id   |             | 
+ salesman_id   | a           | 
  salesman_name |             | 
 (2 rows)
 
 -- New partitions have identity-columns:
 SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans2_3'::regclass::oid;
-    attname    | attidentity | attgenerated 
----------------+-------------+--------------
- salesman_id   | a           | 
- salesman_name |             | 
-(2 rows)
-
+ERROR:  relation "salesmans2_3" does not exist
+LINE 1: ...FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans...
+                                                             ^
 SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans3_4'::regclass::oid;
-    attname    | attidentity | attgenerated 
----------------+-------------+--------------
- salesman_id   | a           | 
- salesman_name |             | 
-(2 rows)
-
+ERROR:  relation "salesmans3_4" does not exist
+LINE 1: ...FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans...
+                                                             ^
 SELECT attname, attidentity, attgenerated FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans4_5'::regclass::oid;
-    attname    | attidentity | attgenerated 
----------------+-------------+--------------
- salesman_id   | a           | 
- salesman_name |             | 
-(2 rows)
-
+ERROR:  relation "salesmans4_5" does not exist
+LINE 1: ...FROM pg_attribute WHERE attnum > 0 AND attrelid = 'salesmans...
+                                                             ^
 DROP TABLE salesmans CASCADE;
 --
 -- Test: split partition with deleted columns
@@ -1121,19 +1115,20 @@
   (PARTITION sales_west FOR VALUES IN ('Voronezh', 'Smolensk', 'Bryansk'),
    PARTITION sales_east FOR VALUES IN ('Magadan', 'Khabarovsk', 'Vladivostok'),
    PARTITION sales_central FOR VALUES IN ('Moscow', 'Kazan', 'Volgograd'));
+ERROR:  no owned sequence found
 SELECT * FROM sales_list;
  salesman_id | salesman_name |  sales_state   | sales_amount | sales_date 
 -------------+---------------+----------------+--------------+------------
+           1 | Trump         | Magadan        |         1000 | 03-01-2022
            2 | Smirnoff      | Smolensk       |          500 | 03-03-2022
-           5 | Deev          | Voronezh       |          250 | 03-07-2022
-          11 | Muller        | Bryansk        |          650 | 03-05-2022
-          14 | Plato         | Voronezh       |          950 | 03-05-2022
            4 | Ivanov        | Moscow         |          750 | 03-04-2022
+           5 | Deev          | Voronezh       |          250 | 03-07-2022
            6 | Poirot        | Kazan          |         1000 | 03-01-2022
+           8 | Li            | Vladivostok    |         1150 | 03-09-2022
+          11 | Muller        | Bryansk        |          650 | 03-05-2022
           12 | Smith         | Volgograd      |          350 | 03-10-2022
           13 | Gandi         | Moscow         |          150 | 03-08-2022
-           1 | Trump         | Magadan        |         1000 | 03-01-2022
-           8 | Li            | Vladivostok    |         1150 | 03-09-2022
+          14 | Plato         | Voronezh       |          950 | 03-05-2022
            3 | Ford          | St. Petersburg |         2000 | 03-05-2022
            7 | May           | Ukhta          |         1200 | 03-06-2022
            9 | May           | Ukhta          |         1200 | 03-11-2022
@@ -1141,21 +1136,13 @@
 (14 rows)
 
 SELECT * FROM sales_west;
- salesman_id | salesman_name | sales_state | sales_amount | sales_date 
--------------+---------------+-------------+--------------+------------
-           2 | Smirnoff      | Smolensk    |          500 | 03-03-2022
-           5 | Deev          | Voronezh    |          250 | 03-07-2022
-          11 | Muller        | Bryansk     |          650 | 03-05-2022
-          14 | Plato         | Voronezh    |          950 | 03-05-2022
-(4 rows)
-
+ERROR:  relation "sales_west" does not exist
+LINE 1: SELECT * FROM sales_west;
+                      ^
 SELECT * FROM sales_east;
- salesman_id | salesman_name | sales_state | sales_amount | sales_date 
--------------+---------------+-------------+--------------+------------
-           1 | Trump         | Magadan     |         1000 | 03-01-2022
-           8 | Li            | Vladivostok |         1150 | 03-09-2022
-(2 rows)
-
+ERROR:  relation "sales_east" does not exist
+LINE 1: SELECT * FROM sales_east;
+                      ^
 SELECT * FROM sales_nord;
  salesman_id | salesman_name |  sales_state   | sales_amount | sales_date 
 -------------+---------------+----------------+--------------+------------
@@ -1166,24 +1153,16 @@
 (4 rows)
 
 SELECT * FROM sales_central;
- salesman_id | salesman_name | sales_state | sales_amount | sales_date 
--------------+---------------+-------------+--------------+------------
-           4 | Ivanov        | Moscow      |          750 | 03-04-2022
-           6 | Poirot        | Kazan       |         1000 | 03-01-2022
-          12 | Smith         | Volgograd   |          350 | 03-10-2022
-          13 | Gandi         | Moscow      |          150 | 03-08-2022
-(4 rows)
-
+ERROR:  relation "sales_central" does not exist
+LINE 1: SELECT * FROM sales_central;
+                      ^
 -- Use indexscan for test indexes after split partition
 SET enable_indexscan = ON;
 SET enable_seqscan = OFF;
 SELECT * FROM sales_central WHERE sales_state = 'Moscow';
- salesman_id | salesman_name | sales_state | sales_amount | sales_date 
--------------+---------------+-------------+--------------+------------
-           4 | Ivanov        | Moscow      |          750 | 03-04-2022
-          13 | Gandi         | Moscow      |          150 | 03-08-2022
-(2 rows)
-
+ERROR:  relation "sales_central" does not exist
+LINE 1: SELECT * FROM sales_central WHERE sales_state = 'Moscow';
+                      ^
 SELECT * FROM sales_list WHERE sales_state = 'Moscow';
  salesman_id | salesman_name | sales_state | sales_amount | sales_date 
 -------------+---------------+-------------+--------------+------------
@@ -1722,3 +1701,6 @@
 DROP TABLE test_2colkey CASCADE;
 --
 DROP SCHEMA partition_split_schema;
+ERROR:  cannot drop schema partition_split_schema because other objects depend on it
+DETAIL:  table salesmans2_5 depends on schema partition_split_schema
+HINT:  Use DROP ... CASCADE to drop the dependent objects too.

---

From: Dmitry Koval <[email-masked]>
Date: Fri, 26 Jan 2024 20:08:08 +0300

git format-patch -4 HEAD -v 23

=============================

Thanks!

I excluded regression test "Test: split partition witch identity column" 
from script src/test/regress/sql/partition_split.sql because after 
commit [1] partitions cannot contain identity columns and queries

CREATE TABLE salesmans2_5(salesman_id INT GENERATED ALWAYS AS IDENTITY 
PRIMARY KEY, salesman_name VARCHAR(30));
ALTER TABLE salesmans ATTACH PARTITION salesmans2_5 FOR VALUES FROM (2) 
TO (5);

returns

ERROR:  table "salesmans2_5" being attached contains an identity column 
"salesman_id"
DETAIL:  The new partition may not contain an identity column.

[1] 
https://github.com/postgres/postgres/commit/699586315704a8268808e3bdba4cb5924a038c49
-- 
With best regards,
Dmitry Koval

From 3041dee1fa86363dbaed12cde1d38f061f5fda1b Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 16:06:03 +0300
Subject: [PATCH v23 1/4] ALTER TABLE MERGE PARTITIONS command

---

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 68f658e834..a44a8156cf 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -662,6 +662,8 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, const char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);

 /* ----------------------------------------------------------------
  *		DefineRelation
@@ -4733,6 +4735,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
+			case AT_MergePartitions:
+				cmd_lockmode = AccessExclusiveLock;
+				break;
+
 			default:			/* oops */
 				elog(ERROR, "unrecognized alter table type: %d",
 					 (int) cmd->subtype);
@@ -5158,6 +5164,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			/* No command-specific prep needed */
 			pass = AT_PASS_MISC;
 			break;
+		case AT_MergePartitions:
+			ATSimplePermissions(cmd->subtype, rel, ATT_TABLE);
+			/* No command-specific prep needed */
+			pass = AT_PASS_MISC;
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -5548,6 +5559,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
 		case AT_DetachPartitionFinalize:
 			address = ATExecDetachPartitionFinalize(rel, ((PartitionCmd *) cmd->def)->name);
 			break;
+		case AT_MergePartitions:
+			cmd = ATParseTransformCmd(wqueue, tab, rel, cmd, false, lockmode,
+									  cur_pass, context);
+			Assert(cmd != NULL);
+			Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
+			ATExecMergePartitions(wqueue, tab, rel, (PartitionCmd *) cmd->def,
+								  context);
+			break;
 		default:				/* oops */
 			elog(ERROR, "unrecognized alter table type: %d",
 				 (int) cmd->subtype);
@@ -6536,6 +6555,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
 			return "DETACH PARTITION";
 		case AT_DetachPartitionFinalize:
 			return "DETACH PARTITION ... FINALIZE";
+		case AT_MergePartitions:
+			return "MERGE PARTITIONS";
 		case AT_AddIdentity:
 			return "ALTER COLUMN ... ADD IDENTITY";
 		case AT_SetIdentity:
@@ -18812,6 +18833,37 @@ QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
 	}
 }
 
+/*
+	CreateInheritance(attachrel, rel, true);
@@ -19014,23 +19066,8 @@ ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd,
 
-	CreateInheritance(attachrel, rel, true);
 
 	/*
 	 * Generate partition constraint from the partition bound specification.
@@ -20584,3 +20621,283 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 
 	return cstorage;
 }
+
+/*
index 130f7fc7c3..4a5b13c300 100644
@@ -744,7 +744,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -2299,6 +2299,7 @@ partition_cmd:
 
@@ -2313,6 +2314,7 @@ partition_cmd:
 					n->subtype = AT_DetachPartition;
 					cmd->name = $3;
 					cmd->bound = NULL;
+					cmd->partlist = NULL;
 					cmd->concurrent = $4;
 					n->def = (Node *) cmd;
 
@@ -2326,6 +2328,21 @@ partition_cmd:
@@ -2342,6 +2359,7 @@ index_partition_cmd:
 
@@ -17324,6 +17342,7 @@ unreserved_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLANS
@@ -17925,6 +17944,7 @@ bare_label_keyword:
 			| PARSER
 			| PARTIAL
 			| PARTITION
+			| PARTITIONS
 			| PASSING
 			| PASSWORD
 			| PLACING
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 56ac4f516e..884a280869 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -58,6 +58,8 @@
 #include "parser/parse_type.h"
 #include "parser/parse_utilcmd.h"
 #include "parser/parser.h"
+#include "partitioning/partdesc.h"
+#include "partitioning/partbounds.h"
 #include "rewrite/rewriteManip.h"
 #include "utils/acl.h"
 #include "utils/builtins.h"
@@ -3404,6 +3406,80 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3674,6 +3750,19 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,

 				/*
index 8a1a5a7255..b3b3aac02a 100644
 
index 476d55dd24..edfe36bf42 100644
 
+/*
 
@@ -2248,6 +2260,7 @@ typedef enum AlterTableType
index 2331acac09..985474df89 100644
index 3d9cc1031f..0329d7bd84 100644
 
index 48563b2cf0..69920757b2 100644
@@ -300,6 +300,9 @@ get_altertable_subcmdinfo(PG_FUNCTION_ARGS)
index 1d8a414eea..6f0236d207 100644
-test: partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats predicate
+test: partition_merge partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats predicate
 
index 7e866e3c3d..e827ed0214 100644
@@ -2578,6 +2578,7 @@ SimpleStats
 SimpleStringList
 SimpleStringListCell
 SingleBoundSortItem
+SinglePartitionSpec
 Size
 SkipPages
 SlabBlock
-- 
2.40.1.windows.1

From 2439724753c8ac6201685a3d34964f9af256aabf Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 17:58:52 +0300
Subject: [PATCH v23 2/4] ALTER TABLE SPLIT PARTITION command

---
 src/test/regress/expected/partition_split.out | 1317 +++++++++++++++++
 src/test/regress/sql/partition_split.sql      |  792 ++++++++++
 16 files changed, 3536 insertions(+), 12 deletions(-)

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index a44a8156cf..b0d2e4af91 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -662,6 +662,9 @@ static void ATDetachCheckNoForeignKeyRefs(Relation partition);
 static char GetAttributeCompression(Oid atttypid, const char *compression);
 static char GetAttributeStorage(Oid atttypid, const char *storagemode);

@@ -4735,6 +4738,10 @@ AlterTableGetLockLevel(List *cmds)
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
@@ -5164,6 +5171,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
@@ -5559,6 +5571,14 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab,
@@ -6555,6 +6575,8 @@ alter_table_type_to_string(AlterTableType cmdtype)
@@ -20622,6 +20644,255 @@ GetAttributeStorage(Oid atttypid, const char *storagemode)
 	return cstorage;
 }
 
+/*
@@ -20676,6 +20947,142 @@ createPartitionTable(RangeVar *newPartName, RangeVar *modelRelName,
 				   NULL);
 }
 
+/*
index 4a5b13c300..6da1f9a076 100644
@@ -643,6 +644,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -759,7 +762,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 
@@ -2289,6 +2292,23 @@ alter_table_cmds:
 			| alter_table_cmds ',' alter_table_cmd	{ $$ = lappend($1, $3); }
 		;
 
+partitions_list:
@@ -2333,6 +2353,20 @@ partition_cmd:
@@ -17407,6 +17441,7 @@ unreserved_keyword:
@@ -18021,6 +18056,7 @@ bare_label_keyword:
index 884a280869..c5a794e237 100644
@@ -3406,6 +3406,43 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
 }

+/*
@@ -3742,7 +3779,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3750,6 +3787,7 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
 
@@ -3758,7 +3796,11 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt,
@@ -4163,13 +4205,13 @@ setSchemaName(const char *context_schema, char **stmt_schema_name)
 
 /*
  * transformPartitionCmd
 
@@ -4178,9 +4220,9 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 
@@ -4188,7 +4230,7 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
index b3b3aac02a..e3504bfe26 100644
 
+/*
 
+/*
index b625f471a8..110c267823 100644
@@ -12653,3 +12653,21 @@ get_range_partbound_string(List *bound_datums)
 
 	return buf->data;
 }
+
+/*
index edfe36bf42..d0ffa3e9de 100644
@@ -2260,6 +2260,7 @@ typedef enum AlterTableType
index 985474df89..89e0a5c504 100644
index 0329d7bd84..9d2a26705f 100644
 
index 161fb5ef02..6d86080622 100644

index 69920757b2..265ef2a547 100644
@@ -300,6 +300,9 @@ get_altertable_subcmdinfo(PG_FUNCTION_ARGS)
index 0000000000..38736d3e67
@@ -0,0 +1,1317 @@
+(salesman_id SERIAL,
index 6f0236d207..117d78cb1b 100644
-test: partition_merge partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats predicate
+test: partition_merge partition_split partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats predicate
 
index 0000000000..e33e616230
@@ -0,0 +1,792 @@
+(salesman_id SERIAL,

From 383fdf8857a9d36bd5350c06d0dfbbe02499504c Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Tue, 28 Mar 2023 10:50:19 +0300
Subject: [PATCH v23 3/4] Documentation for ALTER TABLE SPLIT PARTITION/MERGE
 PARTITIONS commands

---

index 9670671107..9fb31df250 100644

@@ -1106,14 +1113,99 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
     </listitem>
    </varlistentry>

   <para>
@@ -1356,7 +1448,8 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
@@ -1772,6 +1865,31 @@ ALTER TABLE measurement
 
+  <para>
 
  <refsect1>
-- 
2.40.1.windows.1

From d1dd3629e2817ee4d60ce12a0fde5ea9bdaecee0 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Thu, 26 Oct 2023 03:35:24 +0300
Subject: [PATCH v23 4/4] SPLIT PARTITION optimization

---

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index b0d2e4af91..52e8ad2b35 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -20654,20 +20654,47 @@ typedef struct SplitPartitionContext
 	BulkInsertState bistate;	/* state of bulk inserts for partition */
 	TupleTableSlot *dstslot;	/* slot for insert row into partition */
 	Relation	partRel;		/* relation for partition */
+	SinglePartitionSpec *sps;	/* info about single partition (from SQL
+								 * command) */
 }			SplitPartitionContext;
 
+/*
 
 /*

+/*
@@ -20678,67 +20705,66 @@ createSplitPartitionContext(Relation partRel)
 
 /*

 	pfree(pc);
 }
 
 /*

 
 
 		if (sps->bound->is_default)
 		{
 			/* We should not create constraint for detached DEFAULT partition. */
-			defaultPartCtx = pc;
+			si->defaultPartCtx = pc;
 		}
 		else
 		{
@@ -20746,9 +20772,8 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar

@@ -20756,11 +20781,10 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 			 * Map the vars in the constraint expression from rel's attnos to
 			 * splitRel's.
 			 */
-			partConstraint = map_partition_varattnos(partConstraint,
-													 1, splitRel, rel);
+			partConstraint = map_partition_varattnos(partConstraint, 1, splitRel, rel);
 
 			pc->partqualstate =
 
@@ -20768,41 +20792,261 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 		partContexts = lappend(partContexts, pc);
 	}

 
 
 	/*

 	/*
 
 	while (table_scan_getnextslot(scan, ForwardScanDirection, srcslot))
 	{
@@ -20815,7 +21059,7 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 		econtext->ecxt_scantuple = srcslot;

@@ -20836,7 +21080,7 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar
 				ereport(ERROR,
 						(errcode(ERRCODE_CHECK_VIOLATION),
 						 errmsg("can not find partition for split partition row"),
-						 errtable(splitRel)));
+						 errtable(si->splitRel)));
 		}
 
 		if (tuple_map)
@@ -20877,74 +21121,208 @@ moveSplitTableRows(Relation rel, Relation splitRel, List *partlist, List *newPar

 
 
 /*

 
 	/*

 
 /*
@@ -20956,16 +21334,14 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 {
 	Relation	splitRel;
 	Oid			splitRelOid;

@@ -20984,35 +21360,7 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 	splitRelOid = RelationGetRelid(splitRel);

@@ -21033,8 +21381,7 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 
 		/*
@@ -21044,43 +21391,48 @@ ATExecSplitPartition(List **wqueue, AlteredTableInfo *tab, Relation rel,
 		CommandCounterIncrement();
 	}

 

 

 /*
@@ -21226,8 +21578,8 @@ ATExecMergePartitions(List **wqueue, AlteredTableInfo *tab, Relation rel,
 							RelationGetRelationName(pc->partRel))));
 
 		/*
index 38736d3e67..4627a91e57 100644
@@ -1314,4 +1314,311 @@ SELECT * FROM sales_others;
 
 DROP TABLE sales_range;
index e33e616230..0208c0158c 100644
@@ -788,5 +788,157 @@ SELECT * FROM sales_others;
 
 DROP TABLE sales_range;
 
+--
+--

---

From: Dmitry Koval <[email-masked]>
Date: Fri, 26 Jan 2024 21:36:59 +0300

I thought it's wrong to exclude the IDENTITY-column test, so I fixed the 
test and return it back.
Changes in attachment (commit 
v24-0002-ALTER-TABLE-SPLIT-PARTITION-command.patch).

-- 
With best regards,
Dmitry Koval

From 3041dee1fa86363dbaed12cde1d38f061f5fda1b Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 16:06:03 +0300
Subject: [PATCH v24 1/4] ALTER TABLE MERGE PARTITIONS command

---

 

+/*

 	/*
 
 	return cstorage;
 }
+
+/*

 

+/*

 				/*

+/*

 

From 1db0a789f5b714ff6096d0aee043bfc081c2d552 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Mon, 19 Sep 2022 17:58:52 +0300
Subject: [PATCH v24 2/4] ALTER TABLE SPLIT PARTITION command

---

 

+/*
 
+/*

 
+partitions_list:

+/*

 
 /*
  * transformPartitionCmd

 
+/*
 
+/*
 
 	return buf->data;
 }
+
+/*

 
index 0000000000..7eb52f6fee
+CREATE TABLE salesmans2_5(salesman_id INT NOT NULL, salesman_name VARCHAR(30));
 
index 0000000000..40c71889b6
+CREATE TABLE salesmans2_5(salesman_id INT NOT NULL, salesman_name VARCHAR(30));

From ad6223192d8f216fc80a7b687e86ea5a15ac4d67 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Tue, 28 Mar 2023 10:50:19 +0300
Subject: [PATCH v24 3/4] Documentation for ALTER TABLE SPLIT PARTITION/MERGE
 PARTITIONS commands

---

 

   <para>
 
+  <para>
 
  <refsect1>
-- 
2.40.1.windows.1

From 93d21a2b789b1cd75a27017a4645a6dd10b6ec87 Mon Sep 17 00:00:00 2001
From: Koval Dmitry <[email-masked]>
Date: Thu, 26 Oct 2023 03:35:24 +0300
Subject: [PATCH v24 4/4] SPLIT PARTITION optimization

---

+/*
 
 /*

+/*
 
 /*

 	pfree(pc);
 }
 
 /*

 

 
 
 			pc->partqualstate =

 

 	/*

 	/*

 
 
 		if (tuple_map)

 
 
 /*

 
 	/*

 
 /*

 

 		/*

 

 

 /*
 
 		/*
index 7eb52f6fee..a8f3d8d6d1 100644
 
 DROP TABLE sales_range;
index 40c71889b6..17341353e0 100644
 
 DROP TABLE sales_range;
 
+--
+--