default_partition_v14.patch

diff --git a/src/backend/catalog/partition.c b/src/backend/catalog/partition.c
index 7f2fd58..b8217b7 100644
--- a/src/backend/catalog/partition.c
+++ b/src/backend/catalog/partition.c
@@ -35,6 +35,7 @@
 #include "nodes/parsenodes.h"
 #include "optimizer/clauses.h"
 #include "optimizer/planmain.h"
+#include "optimizer/prep.h"
 #include "optimizer/var.h"
 #include "rewrite/rewriteManip.h"
 #include "storage/lmgr.h"
@@ -88,9 +89,12 @@ typedef struct PartitionBoundInfoData
 								 * partitioned table) */
 	int			null_index;		/* Index of the null-accepting partition; -1
 								 * if there isn't one */
+	int			default_index;	/* Index of the default partition if any; -1
+								 * if there isn't one */
 } PartitionBoundInfoData;
 
 #define partition_bound_accepts_nulls(bi) ((bi)->null_index != -1)
+#define partition_bound_has_default(bi) ((bi)->default_index != -1)
 
 /*
  * When qsort'ing partition bounds after reading from the catalog, each bound
@@ -121,14 +125,15 @@ static int32 qsort_partition_rbound_cmp(const void *a, const void *b,
 static Oid get_partition_operator(PartitionKey key, int col,
 					   StrategyNumber strategy, bool *need_relabel);
 static Expr *make_partition_op_expr(PartitionKey key, int keynum,
-					   uint16 strategy, Expr *arg1, Expr *arg2);
+					   uint16 strategy, Expr *arg1, Expr *arg2,
+					   bool is_default);
 static void get_range_key_properties(PartitionKey key, int keynum,
 						 PartitionRangeDatum *ldatum,
 						 PartitionRangeDatum *udatum,
 						 ListCell **partexprs_item,
 						 Expr **keyCol,
 						 Const **lower_val, Const **upper_val);
-static List *get_qual_for_list(PartitionKey key, PartitionBoundSpec *spec);
+static List *get_qual_for_list(Relation parent, PartitionBoundSpec *spec);
 static List *get_qual_for_range(PartitionKey key, PartitionBoundSpec *spec);
 static List *generate_partition_qual(Relation rel);
 
@@ -147,6 +152,8 @@ static int32 partition_bound_cmp(PartitionKey key,
 static int partition_bound_bsearch(PartitionKey key,
 						PartitionBoundInfo boundinfo,
 						void *probe, bool probe_is_bound, bool *is_equal);
+static void check_default_allows_bound(Relation parent,
+						   PartitionBoundSpec *new_spec);
 
 /*
  * RelationBuildPartitionDesc
@@ -174,6 +181,7 @@ RelationBuildPartitionDesc(Relation rel)
 	/* List partitioning specific */
 	PartitionListValue **all_values = NULL;
 	int			null_index = -1;
+	int			default_index = -1;
 
 	/* Range partitioning specific */
 	PartitionRangeBound **rbounds = NULL;
@@ -258,6 +266,12 @@ RelationBuildPartitionDesc(Relation rel)
 					Const	   *val = lfirst(c);
 					PartitionListValue *list_value = NULL;
 
+					if (isDefaultPartitionBound((Node *) lfirst(c)))
+					{
+						default_index = i;
+						continue;
+					}
+
 					if (!val->constisnull)
 					{
 						list_value = (PartitionListValue *)
@@ -504,6 +518,17 @@ RelationBuildPartitionDesc(Relation rel)
 					else
 						boundinfo->null_index = -1;
 
+					/* Assign mapping index for default partition. */
+					if (default_index != -1)
+					{
+						Assert(default_index >= 0 &&
+							   mapping[default_index] == -1);
+						mapping[default_index] = next_index++;
+						boundinfo->default_index = mapping[default_index];
+					}
+					else
+						boundinfo->default_index = -1;
+
 					/* All partition must now have a valid mapping */
 					Assert(next_index == nparts);
 					break;
@@ -559,6 +584,12 @@ RelationBuildPartitionDesc(Relation rel)
 						}
 					}
 					boundinfo->indexes[i] = -1;
+
+					/*
+					 * Currently range partition do not have default partition
+					 * support.
+					 */
+					boundinfo->default_index = -1;
 					break;
 				}
 
@@ -608,6 +639,9 @@ partition_bounds_equal(PartitionKey key,
 	if (b1->null_index != b2->null_index)
 		return false;
 
+	if (b1->default_index != b2->default_index)
+		return false;
+
 	for (i = 0; i < b1->ndatums; i++)
 	{
 		int			j;
@@ -670,6 +704,7 @@ check_new_partition_bound(char *relname, Relation parent, Node *bound)
 	PartitionBoundSpec *spec = (PartitionBoundSpec *) bound;
 	PartitionKey key = RelationGetPartitionKey(parent);
 	PartitionDesc partdesc = RelationGetPartitionDesc(parent);
+	PartitionBoundInfo boundinfo = partdesc->boundinfo;
 	ParseState *pstate = make_parsestate(NULL);
 	int			with = -1;
 	bool		overlap = false;
@@ -682,13 +717,29 @@ check_new_partition_bound(char *relname, Relation parent, Node *bound)
 
 				if (partdesc->nparts > 0)
 				{
-					PartitionBoundInfo boundinfo = partdesc->boundinfo;
 					ListCell   *cell;
 
 					Assert(boundinfo &&
 						   boundinfo->strategy == PARTITION_STRATEGY_LIST &&
 						   (boundinfo->ndatums > 0 ||
-							partition_bound_accepts_nulls(boundinfo)));
+							partition_bound_accepts_nulls(boundinfo) ||
+							partition_bound_has_default(boundinfo)));
+
+					/*
+					 * Default partition cannot be added if there already
+					 * exists one.
+					 */
+					cell = list_head(spec->listdatums);
+					if (cell && isDefaultPartitionBound((Node *) lfirst(cell)))
+					{
+						if (partition_bound_has_default(boundinfo))
+						{
+							overlap = true;
+							with = boundinfo->default_index;
+						}
+
+						break;
+					}
 
 					foreach(cell, spec->listdatums)
 					{
@@ -836,6 +887,139 @@ check_new_partition_bound(char *relname, Relation parent, Node *bound)
 						relname, get_rel_name(partdesc->oids[with])),
 				 parser_errposition(pstate, spec->location)));
 	}
+
+	/*
+	 * If a default partition exists, it's partition constraint will change
+	 * after the addition of this new partition such that it won't allow any
+	 * row that qualifies for this new partition. So, check if the existing
+	 * data in the default partition satisfies this *would be* default
+	 * partition constraint.
+	 */
+	if (partdesc->nparts > 0 && partition_bound_has_default(boundinfo))
+		check_default_allows_bound(parent, spec);
+}
+
+/*
+ * check_default_allows_bound
+ *
+ * Checks if there exists any row in default partition that passes the check
+ * for constraints of new partition, if any reports an error.
+ */
+static void
+check_default_allows_bound(Relation parent, PartitionBoundSpec *new_spec)
+{
+	Relation	default_rel;
+	int			default_index;
+	List	   *new_part_constraints = NIL;
+	List	   *all_parts;
+	ListCell   *lc;
+
+	/* Currently default partition is supported only for LIST partition. */
+	if (new_spec->strategy != PARTITION_STRATEGY_LIST)
+		return;
+
+	new_part_constraints = get_qual_for_list(parent, new_spec);
+	new_part_constraints = (List *) eval_const_expressions(NULL,
+											  (Node *) new_part_constraints);
+	new_part_constraints =
+		(List *) canonicalize_qual((Expr *) new_part_constraints);
+	new_part_constraints = list_make1(make_ands_explicit(new_part_constraints));
+
+	/* Generate the constraint and default execution states. */
+	default_index = parent->rd_partdesc->boundinfo->default_index;
+	default_rel = heap_open(parent->rd_partdesc->oids[default_index],
+							AccessExclusiveLock);
+
+	if (default_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
+		all_parts = find_all_inheritors(RelationGetRelid(default_rel),
+										AccessExclusiveLock, NULL);
+	else
+		all_parts = list_make1_oid(RelationGetRelid(default_rel));
+
+	foreach(lc, all_parts)
+	{
+		Oid			part_relid = lfirst_oid(lc);
+		Relation	part_rel;
+		Expr	   *constr;
+		Expr	   *partition_constraint;
+		EState	   *estate;
+		HeapTuple	tuple;
+		ExprState  *partqualstate = NULL;
+		Snapshot	snapshot;
+		TupleDesc	tupdesc;
+		ExprContext *econtext;
+		HeapScanDesc scan;
+		MemoryContext oldCxt;
+		TupleTableSlot *tupslot;
+
+		/* Lock already taken above. */
+		if (part_relid != RelationGetRelid(default_rel))
+			part_rel = heap_open(part_relid, NoLock);
+		else
+			part_rel = default_rel;
+
+		/*
+		 * Skip if it's a partitioned table. Only RELKIND_RELATION relations
+		 * (ie, leaf partitions) need to be scanned.
+		 */
+		if (part_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
+		{
+			heap_close(part_rel, NoLock);
+			continue;
+		}
+
+		tupdesc = CreateTupleDescCopy(RelationGetDescr(part_rel));
+		constr = linitial(new_part_constraints);
+		partition_constraint = (Expr *) map_partition_varattnos((List *) constr,
+														1, part_rel, parent);
+		estate = CreateExecutorState();
+
+		/* Build expression execution states for partition check quals */
+		partqualstate = ExecPrepareExpr(partition_constraint, estate);
+
+		econtext = GetPerTupleExprContext(estate);
+		snapshot = RegisterSnapshot(GetLatestSnapshot());
+		scan = heap_beginscan(part_rel, snapshot, 0, NULL);
+		tupslot = MakeSingleTupleTableSlot(tupdesc);
+
+		/*
+		 * Switch to per-tuple memory context and reset it for each tuple
+		 * produced, so we don't leak memory.
+		 */
+		oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
+
+		while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
+		{
+			char	   *val_desc;
+
+			ExecStoreTuple(tuple, tupslot, InvalidBuffer, false);
+			econtext->ecxt_scantuple = tupslot;
+
+			if (partqualstate && ExecCheck(partqualstate, econtext))
+			{
+				val_desc =
+					ExecBuildSlotValueDescription(RelationGetRelid(part_rel),
+												  tupslot, tupdesc, NULL, 64);
+
+				ereport(ERROR,
+						(errcode(ERRCODE_CHECK_VIOLATION),
+						 errmsg("new default partition constraint is violated by some row"),
+						 val_desc ?
+					 errdetail("Violating row contains %s.", val_desc) : 0));
+			}
+
+			ResetExprContext(econtext);
+			CHECK_FOR_INTERRUPTS();
+		}
+
+		CacheInvalidateRelcache(part_rel);
+		MemoryContextSwitchTo(oldCxt);
+		heap_endscan(scan);
+		UnregisterSnapshot(snapshot);
+		ExecDropSingleTupleTableSlot(tupslot);
+		FreeExecutorState(estate);
+		heap_close(part_rel, NoLock);
+	}
 }
 
 /*
@@ -884,6 +1068,16 @@ get_partition_parent(Oid relid)
 }
 
 /*
+ * Returns true if the partition bound is default.
+ */
+bool
+isDefaultPartitionBound(Node *value)
+{
+	return (IsA(value, DefElem) &&
+			!strcmp(castNode(DefElem, value)->defname, "default_partition"));
+}
+
+/*
  * get_qual_from_partbound
  *		Given a parser node for partition bound, return the list of executable
  *		expressions as partition constraint
@@ -901,7 +1095,7 @@ get_qual_from_partbound(Relation rel, Relation parent, Node *bound)
 	{
 		case PARTITION_STRATEGY_LIST:
 			Assert(spec->strategy == PARTITION_STRATEGY_LIST);
-			my_qual = get_qual_for_list(key, spec);
+			my_qual = get_qual_for_list(parent, spec);
 			break;
 
 		case PARTITION_STRATEGY_RANGE:
@@ -1231,7 +1425,7 @@ get_partition_operator(PartitionKey key, int col, StrategyNumber strategy,
  */
 static Expr *
 make_partition_op_expr(PartitionKey key, int keynum,
-					   uint16 strategy, Expr *arg1, Expr *arg2)
+					uint16 strategy, Expr *arg1, Expr *arg2, bool is_default)
 {
 	Oid			operoid;
 	bool		need_relabel = false;
@@ -1261,11 +1455,17 @@ make_partition_op_expr(PartitionKey key, int keynum,
 			{
 				ScalarArrayOpExpr *saopexpr;
 
+				if (is_default &&
+					((operoid = get_negator(operoid)) == InvalidOid))
+					ereport(ERROR, (errcode(ERRCODE_RESTRICT_VIOLATION),
+									errmsg("DEFAULT partition cannot be used without negator of operator  %s",
+										   get_opname(operoid))));
+
 				/* Build leftop = ANY (rightop) */
 				saopexpr = makeNode(ScalarArrayOpExpr);
 				saopexpr->opno = operoid;
 				saopexpr->opfuncid = get_opcode(operoid);
-				saopexpr->useOr = true;
+				saopexpr->useOr = !is_default;
 				saopexpr->inputcollid = key->partcollation[keynum];
 				saopexpr->args = list_make2(arg1, arg2);
 				saopexpr->location = -1;
@@ -1297,8 +1497,9 @@ make_partition_op_expr(PartitionKey key, int keynum,
  * Returns a list of expressions to use as a list partition's constraint.
  */
 static List *
-get_qual_for_list(PartitionKey key, PartitionBoundSpec *spec)
+get_qual_for_list(Relation parent, PartitionBoundSpec *spec)
 {
+	PartitionKey key = RelationGetPartitionKey(parent);
 	List	   *result;
 	ArrayExpr  *arr;
 	Expr	   *opexpr;
@@ -1309,6 +1510,9 @@ get_qual_for_list(PartitionKey key, PartitionBoundSpec *spec)
 	bool		list_has_null = false;
 	NullTest   *nulltest1 = NULL,
 			   *nulltest2 = NULL;
+	List	   *listdatums = spec->listdatums;
+	bool		is_default =
+		isDefaultPartitionBound((Node *) linitial(listdatums));
 
 	/* Left operand is either a simple Var or arbitrary expression */
 	if (key->partattrs[0] != 0)
@@ -1322,11 +1526,54 @@ get_qual_for_list(PartitionKey key, PartitionBoundSpec *spec)
 		keyCol = (Expr *) copyObject(linitial(key->partexprs));
 
 	/*
+	 * In case of default partition for list, the partition constraint is
+	 * basically any value that is not equal to any of the values in
+	 * boundinfo->datums array. So, construct a list of constants from
+	 * boundinfo->datums to pass to function make_partition_op_expr via
+	 * ArrayExpr, which would return an negated expression for default
+	 * partition.
+	 */
+	if (is_default)
+	{
+		int			i;
+		int			ndatums = 0;
+		MemoryContext oldcxt;
+		PartitionDesc pdesc = RelationGetPartitionDesc(parent);
+		PartitionBoundInfo boundinfo = pdesc->boundinfo;
+
+		ndatums = (pdesc->nparts > 0) ? boundinfo->ndatums : 0;
+
+		oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
+
+		listdatums = NIL;
+		for (i = 0; i < ndatums; i++)
+		{
+			Const	   *val;
+
+			/* Construct const from datum */
+			val = makeConst(key->parttypid[0],
+							key->parttypmod[0],
+							key->parttypcoll[0],
+							key->parttyplen[0],
+							*boundinfo->datums[i],
+							false,		/* isnull */
+							true /* byval */ );
+
+			listdatums = lappend(listdatums, val);
+		}
+
+		if (boundinfo && partition_bound_accepts_nulls(boundinfo))
+			list_has_null = true;
+
+		MemoryContextSwitchTo(oldcxt);
+	}
+
+	/*
 	 * We must remove any NULL value in the list; we handle it separately
 	 * below.
 	 */
 	prev = NULL;
-	for (cell = list_head(spec->listdatums); cell; cell = next)
+	for (cell = list_head(listdatums); cell && !is_default; cell = next)
 	{
 		Const	   *val = (Const *) lfirst(cell);
 
@@ -1335,14 +1582,13 @@ get_qual_for_list(PartitionKey key, PartitionBoundSpec *spec)
 		if (val->constisnull)
 		{
 			list_has_null = true;
-			spec->listdatums = list_delete_cell(spec->listdatums,
-												cell, prev);
+			listdatums = list_delete_cell(listdatums, cell, prev);
 		}
 		else
 			prev = cell;
 	}
 
-	if (!list_has_null)
+	if ((!list_has_null && !is_default) || (list_has_null && is_default))
 	{
 		/*
 		 * Gin up a col IS NOT NULL test that will be AND'd with other
@@ -1373,13 +1619,13 @@ get_qual_for_list(PartitionKey key, PartitionBoundSpec *spec)
 		: key->parttypid[0];
 	arr->array_collid = key->parttypcoll[0];
 	arr->element_typeid = key->parttypid[0];
-	arr->elements = spec->listdatums;
+	arr->elements = listdatums;
 	arr->multidims = false;
 	arr->location = -1;
 
 	/* Generate the main expression, i.e., keyCol = ANY (arr) */
 	opexpr = make_partition_op_expr(key, 0, BTEqualStrategyNumber,
-									keyCol, (Expr *) arr);
+									keyCol, (Expr *) arr, is_default);
 
 	if (nulltest1)
 		result = list_make2(nulltest1, opexpr);
@@ -1593,7 +1839,7 @@ get_qual_for_range(PartitionKey key, PartitionBoundSpec *spec)
 		oldcxt = MemoryContextSwitchTo(estate->es_query_cxt);
 		test_expr = make_partition_op_expr(key, i, BTEqualStrategyNumber,
 										   (Expr *) lower_val,
-										   (Expr *) upper_val);
+										   (Expr *) upper_val, false);
 		fix_opfuncids((Node *) test_expr);
 		test_exprstate = ExecInitExpr(test_expr, NULL);
 		test_result = ExecEvalExprSwitchContext(test_exprstate,
@@ -1617,7 +1863,7 @@ get_qual_for_range(PartitionKey key, PartitionBoundSpec *spec)
 		/* Equal, so generate keyCol = lower_val expression */
 		result = lappend(result,
 						 make_partition_op_expr(key, i, BTEqualStrategyNumber,
-												keyCol, (Expr *) lower_val));
+										 keyCol, (Expr *) lower_val, false));
 
 		i++;
 	}
@@ -1675,7 +1921,8 @@ get_qual_for_range(PartitionKey key, PartitionBoundSpec *spec)
 											make_partition_op_expr(key, j,
 																   strategy,
 																   keyCol,
-														(Expr *) lower_val));
+														  (Expr *) lower_val,
+																   false));
 			}
 
 			if (need_next_upper_arm && upper_val)
@@ -1697,7 +1944,8 @@ get_qual_for_range(PartitionKey key, PartitionBoundSpec *spec)
 											make_partition_op_expr(key, j,
 																   strategy,
 																   keyCol,
-														(Expr *) upper_val));
+														  (Expr *) upper_val,
+																   false));
 
 			}
 
@@ -2033,10 +2281,26 @@ get_partition_for_tuple(PartitionDispatch *pd,
 		 */
 		if (cur_index < 0)
 		{
-			result = -1;
-			*failed_at = parent;
-			*failed_slot = slot;
-			break;
+			/*
+			 * If partitioned table has a default partition, return its
+			 * sequence number.
+			 */
+			if (partition_bound_has_default(partdesc->boundinfo))
+			{
+				result = parent->indexes[partdesc->boundinfo->default_index];
+
+				if (result >= 0)
+					break;
+				else
+					parent = pd[-result];
+			}
+			else
+			{
+				result = -1;
+				*failed_at = parent;
+				*failed_slot = slot;
+				break;
+			}
 		}
 		else if (parent->indexes[cur_index] >= 0)
 		{
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 4a899f1..dae592a 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -92,11 +92,6 @@ static bool ExecCheckRTEPermsModified(Oid relOid, Oid userid,
 						  Bitmapset *modifiedCols,
 						  AclMode requiredPerms);
 static void ExecCheckXactReadOnly(PlannedStmt *plannedstmt);
-static char *ExecBuildSlotValueDescription(Oid reloid,
-							  TupleTableSlot *slot,
-							  TupleDesc tupdesc,
-							  Bitmapset *modifiedCols,
-							  int maxfieldlen);
 static char *ExecBuildSlotPartitionKeyDescription(Relation rel,
 									 Datum *values,
 									 bool *isnull,
@@ -2174,7 +2169,7 @@ ExecWithCheckOptions(WCOKind kind, ResultRelInfo *resultRelInfo,
  * column involved, that subset will be returned with a key identifying which
  * columns they are.
  */
-static char *
+char *
 ExecBuildSlotValueDescription(Oid reloid,
 							  TupleTableSlot *slot,
 							  TupleDesc tupdesc,
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 2822331..bb59bfc 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -2676,6 +2676,23 @@ ForValues:
 
 					$$ = (Node *) n;
 				}
+
+			/*
+			 * A default partition, that can be partition of either LIST or RANGE
+			 * partitioned table.
+			 * Currently this is supported only for LIST partition.
+			 */
+			| DEFAULT
+				{
+					PartitionBoundSpec *n = makeNode(PartitionBoundSpec);
+
+					n->listdatums =
+						list_make1(makeDefElem("default_partition", NULL, @1));
+					n->location = @1;
+
+					$$ = (Node *) n;
+				}
+
 		;
 
 partbound_datum:
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index beb0995..bbd95d6 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -33,6 +33,7 @@
 #include "catalog/heap.h"
 #include "catalog/index.h"
 #include "catalog/namespace.h"
+#include "catalog/partition.h"
 #include "catalog/pg_am.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
@@ -3310,19 +3311,38 @@ transformPartitionBound(ParseState *pstate, Relation parent, Node *bound)
 										 false, false);
 
 		if (spec->strategy != PARTITION_STRATEGY_LIST)
-			ereport(ERROR,
-					(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
+		{
+			/*
+			 * In case of default partition, parser had no way to identify the
+			 * partition strategy. Assign the parent strategy to default
+			 * partition bound spec.
+			 */
+			if ((list_length(spec->listdatums) == 1) &&
+				isDefaultPartitionBound((Node *) linitial(spec->listdatums)))
+				result_spec->strategy = PARTITION_STRATEGY_LIST;
+			else
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
 				  errmsg("invalid bound specification for a list partition"),
-					 parser_errposition(pstate, exprLocation(bound))));
+						 parser_errposition(pstate, exprLocation(bound))));
+		}
 
 		result_spec->listdatums = NIL;
 		foreach(cell, spec->listdatums)
 		{
 			A_Const    *con = (A_Const *) lfirst(cell);
-			Node	   *value;
+			Node	   *value = lfirst(cell);
 			ListCell   *cell2;
 			bool		duplicate;
 
+			/* Perform the transformation only for non default partition. */
+			if (isDefaultPartitionBound(value))
+			{
+				result_spec->listdatums = lappend(result_spec->listdatums,
+												  value);
+				continue;
+			}
+
 			value = (Node *) make_const(pstate, &con->val, con->location);
 			value = coerce_to_target_type(pstate,
 										  value, exprType(value),
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 9234bc2..fffeb4f 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8652,6 +8652,18 @@ get_rule_expr(Node *node, deparse_context *context,
 					case PARTITION_STRATEGY_LIST:
 						Assert(spec->listdatums != NIL);
 
+						/*
+						 * If the boundspec is of Default partition, it does
+						 * not have list of datums, but has only one node to
+						 * indicate its a default partition.
+						 */
+						if (isDefaultPartitionBound(
+										(Node *) linitial(spec->listdatums)))
+						{
+							appendStringInfoString(buf, "DEFAULT");
+							break;
+						}
+
 						appendStringInfoString(buf, "FOR VALUES");
 						appendStringInfoString(buf, " IN (");
 						sep = "";
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 2abd087..b01ba07 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -2044,7 +2044,7 @@ psql_completion(const char *text, int start, int end)
 		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_tables, "");
 	/* Limited completion support for partition bound specification */
 	else if (TailMatches3("ATTACH", "PARTITION", MatchAny))
-		COMPLETE_WITH_CONST("FOR VALUES");
+		COMPLETE_WITH_LIST2("FOR VALUES", "DEFAULT");
 	else if (TailMatches2("FOR", "VALUES"))
 		COMPLETE_WITH_LIST2("FROM (", "IN (");
 
@@ -2483,7 +2483,7 @@ psql_completion(const char *text, int start, int end)
 		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_partitioned_tables, "");
 	/* Limited completion support for partition bound specification */
 	else if (TailMatches3("PARTITION", "OF", MatchAny))
-		COMPLETE_WITH_CONST("FOR VALUES");
+		COMPLETE_WITH_LIST2("FOR VALUES", "DEFAULT");
 
 /* CREATE TABLESPACE */
 	else if (Matches3("CREATE", "TABLESPACE", MatchAny))
diff --git a/src/include/catalog/partition.h b/src/include/catalog/partition.h
index 25fb0a0..081c1e4 100644
--- a/src/include/catalog/partition.h
+++ b/src/include/catalog/partition.h
@@ -81,6 +81,7 @@ extern List *map_partition_varattnos(List *expr, int target_varno,
 						Relation partrel, Relation parent);
 extern List *RelationGetPartitionQual(Relation rel);
 extern Expr *get_partition_qual_relid(Oid relid);
+extern bool isDefaultPartitionBound(Node *value);
 
 /* For tuple routing */
 extern PartitionDispatch *RelationGetPartitionDispatchInfo(Relation rel,
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index 8cc5f3a..8bd574c 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -537,5 +537,10 @@ extern void CheckCmdReplicaIdentity(Relation rel, CmdType cmd);
 
 extern void CheckSubscriptionRelkind(char relkind, const char *nspname,
 						 const char *relname);
+char *ExecBuildSlotValueDescription(Oid reloid,
+							  TupleTableSlot *slot,
+							  TupleDesc tupdesc,
+							  Bitmapset *modifiedCols,
+							  int maxfieldlen);
 
 #endif   /* EXECUTOR_H  */
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index c88fd76..c31db25 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -3224,6 +3224,11 @@ SELECT conislocal, coninhcount FROM pg_constraint WHERE conrelid = 'part_1'::reg
 CREATE TABLE fail_part (LIKE part_1 INCLUDING CONSTRAINTS);
 ALTER TABLE list_parted ATTACH PARTITION fail_part FOR VALUES IN (1);
 ERROR:  partition "fail_part" would overlap partition "part_1"
+-- attaching default partition overlaps if a default partition already exists
+CREATE TABLE part_def1 PARTITION OF list_parted DEFAULT;
+CREATE TABLE part_def2 (LIKE part_1 INCLUDING CONSTRAINTS);
+ALTER TABLE list_parted ATTACH PARTITION part_def2 DEFAULT;
+ERROR:  partition "part_def2" would overlap partition "part_def1"
 -- check validation when attaching list partitions
 CREATE TABLE list_parted2 (
 	a int,
@@ -3237,6 +3242,16 @@ ERROR:  partition constraint is violated by some row
 -- should be ok after deleting the bad row
 DELETE FROM part_2;
 ALTER TABLE list_parted2 ATTACH PARTITION part_2 FOR VALUES IN (2);
+-- check partition cannot be attached if default has some row for its values
+CREATE TABLE list_parted2_def PARTITION OF list_parted2 DEFAULT;
+INSERT INTO list_parted2_def VALUES (11, 'z');
+CREATE TABLE part_3 (LIKE list_parted2);
+ALTER TABLE list_parted2 ATTACH PARTITION part_3 FOR VALUES IN (11);
+ERROR:  new default partition constraint is violated by some row
+DETAIL:  Violating row contains (11, z).
+-- should be ok after deleting the bad row
+DELETE FROM list_parted2_def WHERE a = 11;
+ALTER TABLE list_parted2 ATTACH PARTITION part_3 FOR VALUES IN (11);
 -- adding constraints that describe the desired partition constraint
 -- (or more restrictive) will help skip the validation scan
 CREATE TABLE part_3_4 (
@@ -3289,9 +3304,22 @@ ALTER TABLE list_parted2 ATTACH PARTITION part_5 FOR VALUES IN (5);
 ERROR:  partition constraint is violated by some row
 -- delete the faulting row and also add a constraint to skip the scan
 DELETE FROM part_5_a WHERE a NOT IN (3);
-ALTER TABLE part_5 ADD CONSTRAINT check_a CHECK (a IN (5)), ALTER a SET NOT NULL;
-ALTER TABLE list_parted2 ATTACH PARTITION part_5 FOR VALUES IN (5);
+ALTER TABLE part_5 ADD CONSTRAINT check_a CHECK (a IN (5, 55)), ALTER a SET NOT NULL;
+ALTER TABLE list_parted2 ATTACH PARTITION part_5 FOR VALUES IN (5, 55);
 INFO:  partition constraint for table "part_5" is implied by existing constraints
+-- check that leaf partitons of default partition are scanned when
+-- attaching a partitioned table.
+ALTER TABLE part_5 DROP CONSTRAINT check_a;
+CREATE TABLE part5_def PARTITION OF part_5 DEFAULT PARTITION BY LIST(a);
+CREATE TABLE part5_def_p1 PARTITION OF part5_def FOR VALUES IN (44, 55);
+INSERT INTO part5_def_p1 VALUES (55, 'y');
+CREATE TABLE part5_p1 (LIKE part_5);
+ALTER TABLE part_5 ATTACH PARTITION part5_p1 FOR VALUES IN ('y');
+ERROR:  new default partition constraint is violated by some row
+DETAIL:  Violating row contains (55, y).
+-- should be ok after deleting the bad row
+DELETE FROM part5_def_p1 WHERE b = 'y';
+ALTER TABLE part_5 ATTACH PARTITION part5_p1 FOR VALUES IN ('y');
 -- check that the table being attached is not already a partition
 ALTER TABLE list_parted2 ATTACH PARTITION part_2 FOR VALUES IN (2);
 ERROR:  "part_2" is already a partition
diff --git a/src/test/regress/expected/create_table.out b/src/test/regress/expected/create_table.out
index 39edf04..2588497 100644
--- a/src/test/regress/expected/create_table.out
+++ b/src/test/regress/expected/create_table.out
@@ -449,6 +449,7 @@ CREATE TABLE list_parted (
 CREATE TABLE part_1 PARTITION OF list_parted FOR VALUES IN ('1');
 CREATE TABLE part_2 PARTITION OF list_parted FOR VALUES IN (2);
 CREATE TABLE part_null PARTITION OF list_parted FOR VALUES IN (null);
+CREATE TABLE part_default PARTITION OF list_parted DEFAULT;
 CREATE TABLE fail_part PARTITION OF list_parted FOR VALUES IN (int '1');
 ERROR:  syntax error at or near "int"
 LINE 1: ... fail_part PARTITION OF list_parted FOR VALUES IN (int '1');
@@ -457,6 +458,8 @@ CREATE TABLE fail_part PARTITION OF list_parted FOR VALUES IN ('1'::int);
 ERROR:  syntax error at or near "::"
 LINE 1: ...fail_part PARTITION OF list_parted FOR VALUES IN ('1'::int);
                                                                 ^
+CREATE TABLE fail_default_part PARTITION OF list_parted DEFAULT;
+ERROR:  partition "fail_default_part" would overlap partition "part_default"
 -- syntax does not allow empty list of values for list partitions
 CREATE TABLE fail_part PARTITION OF list_parted FOR VALUES IN ();
 ERROR:  syntax error at or near ")"
@@ -493,6 +496,11 @@ ERROR:  TO must specify exactly one value per partitioning column
 -- cannot specify null values in range bounds
 CREATE TABLE fail_part PARTITION OF range_parted FOR VALUES FROM (null) TO (unbounded);
 ERROR:  cannot specify NULL in range bound
+-- range partition cannot have default partition
+CREATE TABLE fail_part PARTITION OF range_parted DEFAULT;
+ERROR:  invalid bound specification for a range partition
+LINE 1: CREATE TABLE fail_part PARTITION OF range_parted DEFAULT;
+                                                         ^
 -- cannot specify finite values after UNBOUNDED has been specified
 CREATE TABLE range_parted_multicol (a int, b int, c int) PARTITION BY RANGE (a, b, c);
 CREATE TABLE fail_part PARTITION OF range_parted_multicol FOR VALUES FROM (1, UNBOUNDED, 1) TO (UNBOUNDED, 1, 1);
@@ -544,10 +552,16 @@ CREATE TABLE list_parted2 (
 ) PARTITION BY LIST (a);
 CREATE TABLE part_null_z PARTITION OF list_parted2 FOR VALUES IN (null, 'z');
 CREATE TABLE part_ab PARTITION OF list_parted2 FOR VALUES IN ('a', 'b');
+CREATE TABLE list_parted2_def PARTITION OF list_parted2 DEFAULT;
 CREATE TABLE fail_part PARTITION OF list_parted2 FOR VALUES IN (null);
 ERROR:  partition "fail_part" would overlap partition "part_null_z"
 CREATE TABLE fail_part PARTITION OF list_parted2 FOR VALUES IN ('b', 'c');
 ERROR:  partition "fail_part" would overlap partition "part_ab"
+-- check default partition overlap
+INSERT INTO list_parted2 VALUES('X');
+CREATE TABLE fail_part PARTITION OF list_parted2 FOR VALUES IN ('W', 'X', 'Y');
+ERROR:  new default partition constraint is violated by some row
+DETAIL:  Violating row contains (X).
 CREATE TABLE range_parted2 (
 	a int
 ) PARTITION BY RANGE (a);
diff --git a/src/test/regress/expected/insert.out b/src/test/regress/expected/insert.out
index 8b0752a..841f7c3 100644
--- a/src/test/regress/expected/insert.out
+++ b/src/test/regress/expected/insert.out
@@ -202,6 +202,7 @@ create table list_parted (
 create table part_aa_bb partition of list_parted FOR VALUES IN ('aa', 'bb');
 create table part_cc_dd partition of list_parted FOR VALUES IN ('cc', 'dd');
 create table part_null partition of list_parted FOR VALUES IN (null);
+create table part_default partition of list_parted default;
 -- fail
 insert into part_aa_bb values ('cc', 1);
 ERROR:  new row for relation "part_aa_bb" violates partition constraint
@@ -212,24 +213,46 @@ DETAIL:  Failing row contains (AAa, 1).
 insert into part_aa_bb values (null);
 ERROR:  new row for relation "part_aa_bb" violates partition constraint
 DETAIL:  Failing row contains (null, null).
+insert into part_default values ('aa', 2);
+ERROR:  new row for relation "part_default" violates partition constraint
+DETAIL:  Failing row contains (aa, 2).
+insert into part_default values (null, 2);
+ERROR:  new row for relation "part_default" violates partition constraint
+DETAIL:  Failing row contains (null, 2).
 -- ok
 insert into part_cc_dd values ('cC', 1);
 insert into part_null values (null, 0);
+insert into part_default values ('Zz', 2);
 -- check in case of multi-level partitioned table
 create table part_ee_ff partition of list_parted for values in ('ee', 'ff') partition by range (b);
 create table part_ee_ff1 partition of part_ee_ff for values from (1) to (10);
 create table part_ee_ff2 partition of part_ee_ff for values from (10) to (20);
+-- check in case of multi-level default partitioned table
+drop table part_default;
+create table part_default partition of list_parted default partition by range(b);
+create table part_default_p1 partition of part_default for values from (20) to (30);
+create table part_default_p2 partition of part_default for values from (30) to (40);
 -- fail
 insert into part_ee_ff1 values ('EE', 11);
 ERROR:  new row for relation "part_ee_ff1" violates partition constraint
 DETAIL:  Failing row contains (EE, 11).
+insert into part_default_p2 values ('gg', 43);
+ERROR:  new row for relation "part_default_p2" violates partition constraint
+DETAIL:  Failing row contains (gg, 43).
 -- fail (even the parent's, ie, part_ee_ff's partition constraint applies)
 insert into part_ee_ff1 values ('cc', 1);
 ERROR:  new row for relation "part_ee_ff1" violates partition constraint
 DETAIL:  Failing row contains (cc, 1).
+insert into part_default values ('gg', 43);
+ERROR:  no partition of relation "part_default" found for row
+DETAIL:  Partition key of the failing row contains (b) = (43).
 -- ok
 insert into part_ee_ff1 values ('ff', 1);
 insert into part_ee_ff2 values ('ff', 11);
+insert into part_default_p1 values ('cd', 25);
+insert into part_default_p2 values ('gg', 35);
+insert into list_parted values ('ab', 21);
+drop table part_default;
 -- Check tuple routing for partitioned tables
 -- fail
 insert into range_parted values ('a', 0);
diff --git a/src/test/regress/expected/update.out b/src/test/regress/expected/update.out
index 9366f04..0f41e7e 100644
--- a/src/test/regress/expected/update.out
+++ b/src/test/regress/expected/update.out
@@ -218,5 +218,24 @@ ERROR:  new row for relation "part_b_10_b_20" violates partition constraint
 DETAIL:  Failing row contains (b, 9).
 -- ok
 update range_parted set b = b + 1 where b = 10;
+create table list_parted (
+	a text,
+	b int
+) partition by list (a);
+create table list_part1  partition of list_parted for values in ('a', 'b');
+create table list_default partition of list_parted default;
+insert into list_part1 values ('a', 1);
+insert into list_default values ('d', 10);
+-- fail
+update list_part1 set a = 'c' where a = 'a';
+ERROR:  new row for relation "list_part1" violates partition constraint
+DETAIL:  Failing row contains (c, 1).
+update list_default set a = 'a' where a = 'd';
+ERROR:  new row for relation "list_default" violates partition constraint
+DETAIL:  Failing row contains (a, 10).
+-- ok
+update list_part1 set a = 'b' where a = 'a';
+update list_default set a = 'x' where a = 'd';
 -- cleanup
 drop table range_parted;
+drop table list_parted;
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index c0e2972..dab3cfa 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -2075,6 +2075,10 @@ SELECT conislocal, coninhcount FROM pg_constraint WHERE conrelid = 'part_1'::reg
 -- check that the new partition won't overlap with an existing partition
 CREATE TABLE fail_part (LIKE part_1 INCLUDING CONSTRAINTS);
 ALTER TABLE list_parted ATTACH PARTITION fail_part FOR VALUES IN (1);
+-- attaching default partition overlaps if a default partition already exists
+CREATE TABLE part_def1 PARTITION OF list_parted DEFAULT;
+CREATE TABLE part_def2 (LIKE part_1 INCLUDING CONSTRAINTS);
+ALTER TABLE list_parted ATTACH PARTITION part_def2 DEFAULT;
 
 -- check validation when attaching list partitions
 CREATE TABLE list_parted2 (
@@ -2091,6 +2095,15 @@ ALTER TABLE list_parted2 ATTACH PARTITION part_2 FOR VALUES IN (2);
 DELETE FROM part_2;
 ALTER TABLE list_parted2 ATTACH PARTITION part_2 FOR VALUES IN (2);
 
+-- check partition cannot be attached if default has some row for its values
+CREATE TABLE list_parted2_def PARTITION OF list_parted2 DEFAULT;
+INSERT INTO list_parted2_def VALUES (11, 'z');
+CREATE TABLE part_3 (LIKE list_parted2);
+ALTER TABLE list_parted2 ATTACH PARTITION part_3 FOR VALUES IN (11);
+-- should be ok after deleting the bad row
+DELETE FROM list_parted2_def WHERE a = 11;
+ALTER TABLE list_parted2 ATTACH PARTITION part_3 FOR VALUES IN (11);
+
 -- adding constraints that describe the desired partition constraint
 -- (or more restrictive) will help skip the validation scan
 CREATE TABLE part_3_4 (
@@ -2149,9 +2162,20 @@ ALTER TABLE list_parted2 ATTACH PARTITION part_5 FOR VALUES IN (5);
 
 -- delete the faulting row and also add a constraint to skip the scan
 DELETE FROM part_5_a WHERE a NOT IN (3);
-ALTER TABLE part_5 ADD CONSTRAINT check_a CHECK (a IN (5)), ALTER a SET NOT NULL;
-ALTER TABLE list_parted2 ATTACH PARTITION part_5 FOR VALUES IN (5);
-
+ALTER TABLE part_5 ADD CONSTRAINT check_a CHECK (a IN (5, 55)), ALTER a SET NOT NULL;
+ALTER TABLE list_parted2 ATTACH PARTITION part_5 FOR VALUES IN (5, 55);
+
+-- check that leaf partitons of default partition are scanned when
+-- attaching a partitioned table.
+ALTER TABLE part_5 DROP CONSTRAINT check_a;
+CREATE TABLE part5_def PARTITION OF part_5 DEFAULT PARTITION BY LIST(a);
+CREATE TABLE part5_def_p1 PARTITION OF part5_def FOR VALUES IN (44, 55);
+INSERT INTO part5_def_p1 VALUES (55, 'y');
+CREATE TABLE part5_p1 (LIKE part_5);
+ALTER TABLE part_5 ATTACH PARTITION part5_p1 FOR VALUES IN ('y');
+-- should be ok after deleting the bad row
+DELETE FROM part5_def_p1 WHERE b = 'y';
+ALTER TABLE part_5 ATTACH PARTITION part5_p1 FOR VALUES IN ('y');
 
 -- check that the table being attached is not already a partition
 ALTER TABLE list_parted2 ATTACH PARTITION part_2 FOR VALUES IN (2);
diff --git a/src/test/regress/sql/create_table.sql b/src/test/regress/sql/create_table.sql
index 5a27743..31cbab1 100644
--- a/src/test/regress/sql/create_table.sql
+++ b/src/test/regress/sql/create_table.sql
@@ -439,8 +439,10 @@ CREATE TABLE list_parted (
 CREATE TABLE part_1 PARTITION OF list_parted FOR VALUES IN ('1');
 CREATE TABLE part_2 PARTITION OF list_parted FOR VALUES IN (2);
 CREATE TABLE part_null PARTITION OF list_parted FOR VALUES IN (null);
+CREATE TABLE part_default PARTITION OF list_parted DEFAULT;
 CREATE TABLE fail_part PARTITION OF list_parted FOR VALUES IN (int '1');
 CREATE TABLE fail_part PARTITION OF list_parted FOR VALUES IN ('1'::int);
+CREATE TABLE fail_default_part PARTITION OF list_parted DEFAULT;
 
 -- syntax does not allow empty list of values for list partitions
 CREATE TABLE fail_part PARTITION OF list_parted FOR VALUES IN ();
@@ -467,6 +469,8 @@ CREATE TABLE fail_part PARTITION OF range_parted FOR VALUES FROM ('a') TO ('z',
 
 -- cannot specify null values in range bounds
 CREATE TABLE fail_part PARTITION OF range_parted FOR VALUES FROM (null) TO (unbounded);
+-- range partition cannot have default partition
+CREATE TABLE fail_part PARTITION OF range_parted DEFAULT;
 
 -- cannot specify finite values after UNBOUNDED has been specified
 CREATE TABLE range_parted_multicol (a int, b int, c int) PARTITION BY RANGE (a, b, c);
@@ -512,9 +516,13 @@ CREATE TABLE list_parted2 (
 ) PARTITION BY LIST (a);
 CREATE TABLE part_null_z PARTITION OF list_parted2 FOR VALUES IN (null, 'z');
 CREATE TABLE part_ab PARTITION OF list_parted2 FOR VALUES IN ('a', 'b');
+CREATE TABLE list_parted2_def PARTITION OF list_parted2 DEFAULT;
 
 CREATE TABLE fail_part PARTITION OF list_parted2 FOR VALUES IN (null);
 CREATE TABLE fail_part PARTITION OF list_parted2 FOR VALUES IN ('b', 'c');
+-- check default partition overlap
+INSERT INTO list_parted2 VALUES('X');
+CREATE TABLE fail_part PARTITION OF list_parted2 FOR VALUES IN ('W', 'X', 'Y');
 
 CREATE TABLE range_parted2 (
 	a int
diff --git a/src/test/regress/sql/insert.sql b/src/test/regress/sql/insert.sql
index db8967b..a9f2289 100644
--- a/src/test/regress/sql/insert.sql
+++ b/src/test/regress/sql/insert.sql
@@ -118,27 +118,42 @@ create table list_parted (
 create table part_aa_bb partition of list_parted FOR VALUES IN ('aa', 'bb');
 create table part_cc_dd partition of list_parted FOR VALUES IN ('cc', 'dd');
 create table part_null partition of list_parted FOR VALUES IN (null);
+create table part_default partition of list_parted default;
 
 -- fail
 insert into part_aa_bb values ('cc', 1);
 insert into part_aa_bb values ('AAa', 1);
 insert into part_aa_bb values (null);
+insert into part_default values ('aa', 2);
+insert into part_default values (null, 2);
 -- ok
 insert into part_cc_dd values ('cC', 1);
 insert into part_null values (null, 0);
+insert into part_default values ('Zz', 2);
 
 -- check in case of multi-level partitioned table
 create table part_ee_ff partition of list_parted for values in ('ee', 'ff') partition by range (b);
 create table part_ee_ff1 partition of part_ee_ff for values from (1) to (10);
 create table part_ee_ff2 partition of part_ee_ff for values from (10) to (20);
+-- check in case of multi-level default partitioned table
+drop table part_default;
+create table part_default partition of list_parted default partition by range(b);
+create table part_default_p1 partition of part_default for values from (20) to (30);
+create table part_default_p2 partition of part_default for values from (30) to (40);
 
 -- fail
 insert into part_ee_ff1 values ('EE', 11);
+insert into part_default_p2 values ('gg', 43);
 -- fail (even the parent's, ie, part_ee_ff's partition constraint applies)
 insert into part_ee_ff1 values ('cc', 1);
+insert into part_default values ('gg', 43);
 -- ok
 insert into part_ee_ff1 values ('ff', 1);
 insert into part_ee_ff2 values ('ff', 11);
+insert into part_default_p1 values ('cd', 25);
+insert into part_default_p2 values ('gg', 35);
+insert into list_parted values ('ab', 21);
+drop table part_default;
 
 -- Check tuple routing for partitioned tables
 
diff --git a/src/test/regress/sql/update.sql b/src/test/regress/sql/update.sql
index 6637119..02840a4 100644
--- a/src/test/regress/sql/update.sql
+++ b/src/test/regress/sql/update.sql
@@ -125,5 +125,22 @@ update range_parted set b = b - 1 where b = 10;
 -- ok
 update range_parted set b = b + 1 where b = 10;
 
+create table list_parted (
+	a text,
+	b int
+) partition by list (a);
+create table list_part1  partition of list_parted for values in ('a', 'b');
+create table list_default partition of list_parted default;
+insert into list_part1 values ('a', 1);
+insert into list_default values ('d', 10);
+
+-- fail
+update list_part1 set a = 'c' where a = 'a';
+update list_default set a = 'a' where a = 'd';
+-- ok
+update list_part1 set a = 'b' where a = 'a';
+update list_default set a = 'x' where a = 'd';
+
 -- cleanup
 drop table range_parted;
+drop table list_parted;