Recovery control functions

diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index 17a1d34..5b90e9e 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -42,7 +42,8 @@ ALTER TABLE <replaceable class="PARAMETER">name</replaceable>
     ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> SET ( <replaceable class="PARAMETER">attribute_option</replaceable> = <replaceable class="PARAMETER">value</replaceable> [, ... ] )
     ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> RESET ( <replaceable class="PARAMETER">attribute_option</replaceable> [, ... ] )
     ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> SET STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN }
-    ADD <replaceable class="PARAMETER">table_constraint</replaceable>
+    ADD <replaceable class="PARAMETER">table_constraint</replaceable> [ NOT VALID ]
+    VALIDATE CONSTRAINT <replaceable class="PARAMETER">constraint_name</replaceable>
     DROP CONSTRAINT [ IF EXISTS ]  <replaceable class="PARAMETER">constraint_name</replaceable> [ RESTRICT | CASCADE ]
     DISABLE TRIGGER [ <replaceable class="PARAMETER">trigger_name</replaceable> | ALL | USER ]
     ENABLE TRIGGER [ <replaceable class="PARAMETER">trigger_name</replaceable> | ALL | USER ]
@@ -220,11 +221,27 @@ ALTER TABLE <replaceable class="PARAMETER">name</replaceable>
    </varlistentry>
 
    <varlistentry>
-    <term><literal>ADD <replaceable class="PARAMETER">table_constraint</replaceable></literal></term>
+    <term><literal>ADD <replaceable class="PARAMETER">table_constraint</replaceable>
+          [ NOT VALID ]</literal></term>
     <listitem>
      <para>
       This form adds a new constraint to a table using the same syntax as
-      <xref linkend="SQL-CREATETABLE">.
+      <xref linkend="SQL-CREATETABLE">. Newly added foreign key constraints can
+      also be defined as <literal>NOT VALID</literal> to avoid the
+      potentially lengthy initial check that must otherwise be performed.
+      Constraint checks are skipped at create table time, so
+      <xref linkend="SQL-CREATETABLE"> does not contain this option.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>VALIDATE CONSTRAINT</literal></term>
+    <listitem>
+     <para>
+      This form validates a foreign key constraint that was previously created
+      as <literal>NOT VALID</literal>. Constraints already marked valid do not
+      cause an error response.
      </para>
     </listitem>
    </varlistentry>
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index 4c55db7..7cc521d 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -1835,6 +1835,7 @@ StoreRelCheck(Relation rel, char *ccname, Node *expr,
 						  CONSTRAINT_CHECK,		/* Constraint Type */
 						  false,	/* Is Deferrable */
 						  false,	/* Is Deferred */
+						  true,		/* Is Validated */
 						  RelationGetRelid(rel),		/* relation */
 						  attNos,		/* attrs in the constraint */
 						  keycount,		/* # attrs in the constraint */
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index 4dd89e1..a19b139 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -777,6 +777,7 @@ index_create(Oid heapRelationId,
 										   constraintType,
 										   deferrable,
 										   initdeferred,
+										   true,
 										   heapRelationId,
 										   indexInfo->ii_KeyAttrNumbers,
 										   indexInfo->ii_NumIndexAttrs,
diff --git a/src/backend/catalog/pg_constraint.c b/src/backend/catalog/pg_constraint.c
index 3a38518..6619eed 100644
--- a/src/backend/catalog/pg_constraint.c
+++ b/src/backend/catalog/pg_constraint.c
@@ -46,6 +46,7 @@ CreateConstraintEntry(const char *constraintName,
 					  char constraintType,
 					  bool isDeferrable,
 					  bool isDeferred,
+					  bool isValidated,
 					  Oid relId,
 					  const int16 *constraintKey,
 					  int constraintNKeys,
@@ -158,6 +159,7 @@ CreateConstraintEntry(const char *constraintName,
 	values[Anum_pg_constraint_contype - 1] = CharGetDatum(constraintType);
 	values[Anum_pg_constraint_condeferrable - 1] = BoolGetDatum(isDeferrable);
 	values[Anum_pg_constraint_condeferred - 1] = BoolGetDatum(isDeferred);
+	values[Anum_pg_constraint_convalidated - 1] = BoolGetDatum(isValidated);
 	values[Anum_pg_constraint_conrelid - 1] = ObjectIdGetDatum(relId);
 	values[Anum_pg_constraint_contypid - 1] = ObjectIdGetDatum(domainId);
 	values[Anum_pg_constraint_conindid - 1] = ObjectIdGetDatum(indexRelId);
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index f3bd565..8041a9b 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -254,6 +254,7 @@ static void AlterIndexNamespaces(Relation classRel, Relation rel,
 static void AlterSeqNamespaces(Relation classRel, Relation rel,
 				   Oid oldNspOid, Oid newNspOid,
 				   const char *newNspName, LOCKMODE lockmode);
+static void ATExecValidateConstraint(Relation rel, const char *constrName);
 static int transformColumnNameList(Oid relId, List *colList,
 						int16 *attnums, Oid *atttypids);
 static int transformFkeyGetPrimaryKey(Relation pkrel, Oid *indexOid,
@@ -264,9 +265,9 @@ static Oid transformFkeyCheckAttrs(Relation pkrel,
 						int numattrs, int16 *attnums,
 						Oid *opclasses);
 static void checkFkeyPermissions(Relation rel, int16 *attnums, int natts);
-static void validateForeignKeyConstraint(Constraint *fkconstraint,
+static void validateForeignKeyConstraint(char *conname,
 							 Relation rel, Relation pkrel,
-							 Oid pkindOid, Oid constraintOid);
+							 Oid pkindOid, Oid constraintOid, bool must_use_query);
 static void createForeignKeyTriggers(Relation rel, Constraint *fkconstraint,
 						 Oid constraintOid, Oid indexOid);
 static void ATController(Relation rel, List *cmds, bool recurse, LOCKMODE lockmode);
@@ -2646,7 +2647,7 @@ AlterTableGetLockLevel(List *cmds)
 			 * though don't change the semantic results from normal data reads and writes.
 			 * Delaying an ALTER TABLE behind currently active writes only delays the point
 			 * where the new strategy begins to take effect, so there is no benefit in waiting.
-			 * In thise case the minimum restriction applies: we don't currently allow
+			 * In these case the minimum restriction applies: we don't currently allow
 			 * concurrent catalog updates.
 			 */
 			case AT_SetStatistics:
@@ -2657,6 +2658,7 @@ AlterTableGetLockLevel(List *cmds)
 			case AT_SetOptions:
 			case AT_ResetOptions:
 			case AT_SetStorage:
+			case AT_ValidateConstraint:
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
 
@@ -2878,6 +2880,7 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			ATPrepAddInherit(rel);
 			pass = AT_PASS_MISC;
 			break;
+		case AT_ValidateConstraint:
 		case AT_EnableTrig:		/* ENABLE TRIGGER variants */
 		case AT_EnableAlwaysTrig:
 		case AT_EnableReplicaTrig:
@@ -3042,6 +3045,9 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
 			ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
 								true, lockmode);
 			break;
+		case AT_ValidateConstraint:
+			ATExecValidateConstraint(rel, cmd->name);
+			break;
 		case AT_DropConstraint:	/* DROP CONSTRAINT */
 			ATExecDropConstraint(rel, cmd->name, cmd->behavior,
 								 false, false,
@@ -3294,9 +3300,15 @@ ATRewriteTables(List **wqueue, LOCKMODE lockmode)
 				 */
 				refrel = heap_open(con->refrelid, ShareRowExclusiveLock);
 
-				validateForeignKeyConstraint(fkconstraint, rel, refrel,
+				validateForeignKeyConstraint(fkconstraint->conname, rel, refrel,
 											 con->refindid,
-											 con->conid);
+											 con->conid,
+											 false);
+
+				/*
+				 * No need to mark the constraint row as validated,
+				 * we did that when we inserted the row earlier.
+				 */
 
 				heap_close(refrel, NoLock);
 			}
@@ -5422,6 +5434,7 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
 									  CONSTRAINT_FOREIGN,
 									  fkconstraint->deferrable,
 									  fkconstraint->initdeferred,
+									  !fkconstraint->skip_validation,
 									  RelationGetRelid(rel),
 									  fkattnum,
 									  numfks,
@@ -5451,7 +5464,8 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
 
 	/*
 	 * Tell Phase 3 to check that the constraint is satisfied by existing rows
-	 * (we can skip this during table creation).
+	 * We can skip this during table creation or if requested explicitly
+	 * by specifying NOT VALID on an alter table statement.
 	 */
 	if (!fkconstraint->skip_validation)
 	{
@@ -5474,6 +5488,81 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
 	heap_close(pkrel, NoLock);
 }
 
+/*
+ * ALTER TABLE VALIDATE CONSTRAINT
+ */
+static void
+ATExecValidateConstraint(Relation rel, const char *constrName)
+{
+	Relation	conrel;
+	Form_pg_constraint con;
+	SysScanDesc scan;
+	ScanKeyData key;
+	HeapTuple	tuple;
+	bool		found = false;
+	Oid			conid;
+
+	conrel = heap_open(ConstraintRelationId, RowExclusiveLock);
+
+	/*
+	 * Find and the target constraint
+	 */
+	ScanKeyInit(&key,
+				Anum_pg_constraint_conrelid,
+				BTEqualStrategyNumber, F_OIDEQ,
+				ObjectIdGetDatum(RelationGetRelid(rel)));
+	scan = systable_beginscan(conrel, ConstraintRelidIndexId,
+							  true, SnapshotNow, 1, &key);
+
+	while (HeapTupleIsValid(tuple = systable_getnext(scan)))
+	{
+		con = (Form_pg_constraint) GETSTRUCT(tuple);
+
+		if (strcmp(NameStr(con->conname), constrName) != 0)
+			continue;
+
+		conid = HeapTupleGetOid(tuple);
+		found = true;
+		break;
+	}
+
+	if (found && con->contype == CONSTR_FOREIGN && !con->convalidated)
+	{
+		Relation	refrel;
+
+		/*
+		 * Triggers are already in place on both tables, so a
+		 * concurrent write that alters the result here is not
+		 * possible.
+		 */
+		refrel = heap_open(con->confrelid, AccessShareLock);
+
+		validateForeignKeyConstraint((char *)constrName, rel, refrel,
+									 con->conindid,
+									 conid,
+									 true); /* must use query */
+
+		/*
+		 * Now update the catalog, while we have the door open.
+		 */
+		con->convalidated = BoolGetDatum(true);
+		simple_heap_update(conrel, &tuple->t_self, tuple);
+		CatalogUpdateIndexes(conrel, tuple);
+
+		heap_close(refrel, NoLock);
+	}
+
+	systable_endscan(scan);
+	heap_close(conrel, RowExclusiveLock);
+
+	if (!found)
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+			errmsg("foreign key constraint \"%s\" of relation \"%s\" does not exist",
+				   constrName, RelationGetRelationName(rel))));
+	}
+}
 
 /*
  * transformColumnNameList - transform list of column names
@@ -5779,11 +5868,12 @@ checkFkeyPermissions(Relation rel, int16 *attnums, int natts)
  * Caller must have opened and locked both relations appropriately.
  */
 static void
-validateForeignKeyConstraint(Constraint *fkconstraint,
+validateForeignKeyConstraint(char *conname,
 							 Relation rel,
 							 Relation pkrel,
 							 Oid pkindOid,
-							 Oid constraintOid)
+							 Oid constraintOid,
+							 bool must_use_query)
 {
 	HeapScanDesc scan;
 	HeapTuple	tuple;
@@ -5794,7 +5884,7 @@ validateForeignKeyConstraint(Constraint *fkconstraint,
 	 */
 	MemSet(&trig, 0, sizeof(trig));
 	trig.tgoid = InvalidOid;
-	trig.tgname = fkconstraint->conname;
+	trig.tgname = conname;
 	trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
 	trig.tgisinternal = TRUE;
 	trig.tgconstrrelid = RelationGetRelid(pkrel);
@@ -5811,6 +5901,12 @@ validateForeignKeyConstraint(Constraint *fkconstraint,
 	if (RI_Initial_Check(&trig, rel, pkrel))
 		return;
 
+	if (must_use_query)
+		ereport(ERROR,
+				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+				 errmsg("cannot SELECT from primary key of relation \"%s\"",
+						RelationGetRelationName(rel))));
+
 	/*
 	 * Scan through each tuple, calling RI_FKey_check_ins (insert trigger) as
 	 * if that tuple had just been inserted.  If any of those fail, it should
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index 4802138..8d996a8 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -422,6 +422,7 @@ CreateTrigger(CreateTrigStmt *stmt, const char *queryString,
 											  CONSTRAINT_TRIGGER,
 											  stmt->deferrable,
 											  stmt->initdeferred,
+											  true,
 											  RelationGetRelid(rel),
 											  NULL,		/* no conkey */
 											  0,
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 113bede..840cb81 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -2377,6 +2377,7 @@ domainAddConstraint(Oid domainOid, Oid domainNamespace, Oid baseTypeOid,
 						  CONSTRAINT_CHECK,		/* Constraint Type */
 						  false,	/* Is Deferrable */
 						  false,	/* Is Deferred */
+						  true,		/* Is Validated */
 						  InvalidOid,	/* not a relation constraint */
 						  NULL,
 						  0,
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 660947c..2881211 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -545,7 +545,7 @@ static RangeVar *makeRangeVarFromAnyName(List *names, int position, core_yyscan_
 	UNBOUNDED UNCOMMITTED UNENCRYPTED UNION UNIQUE UNKNOWN UNLISTEN UNLOGGED
 	UNTIL UPDATE USER USING
 
-	VACUUM VALID VALIDATOR VALUE_P VALUES VARCHAR VARIADIC VARYING
+	VACUUM VALID VALIDATE VALIDATOR VALUE_P VALUES VARCHAR VARIADIC VARYING
 	VERBOSE VERSION_P VIEW VOLATILE
 
 	WHEN WHERE WHITESPACE_P WINDOW WITH WITHOUT WORK WRAPPER WRITE
@@ -1751,6 +1751,14 @@ alter_table_cmd:
 					n->def = $2;
 					$$ = (Node *)n;
 				}
+			/* ALTER TABLE <name> VALIDATE CONSTRAINT ... */
+			| VALIDATE CONSTRAINT name
+				{
+					AlterTableCmd *n = makeNode(AlterTableCmd);
+					n->subtype = AT_ValidateConstraint;
+					n->name = $3;
+					$$ = (Node *)n;
+				}
 			/* ALTER TABLE <name> DROP CONSTRAINT IF EXISTS <name> [RESTRICT|CASCADE] */
 			| DROP CONSTRAINT IF_P EXISTS name opt_drop_behavior
 				{
@@ -2711,9 +2719,25 @@ ConstraintElem:
 					n->fk_matchtype		= $9;
 					n->fk_upd_action	= (char) ($10 >> 8);
 					n->fk_del_action	= (char) ($10 & 0xFF);
-					n->skip_validation  = FALSE;
 					n->deferrable		= ($11 & 1) != 0;
 					n->initdeferred		= ($11 & 2) != 0;
+					n->skip_validation  = false;
+					$$ = (Node *)n;
+				}
+			| FOREIGN KEY '(' columnList ')' REFERENCES qualified_name
+				opt_column_list key_match key_actions
+				NOT VALID
+				{
+					Constraint *n = makeNode(Constraint);
+					n->contype = CONSTR_FOREIGN;
+					n->location = @1;
+					n->pktable			= $7;
+					n->fk_attrs			= $4;
+					n->pk_attrs			= $8;
+					n->fk_matchtype		= $9;
+					n->fk_upd_action	= (char) ($10 >> 8);
+					n->fk_del_action	= (char) ($10 & 0xFF);
+					n->skip_validation  = true;
 					$$ = (Node *)n;
 				}
 		;
diff --git a/src/include/catalog/pg_constraint.h b/src/include/catalog/pg_constraint.h
index 26dbcac..a7967ab 100644
--- a/src/include/catalog/pg_constraint.h
+++ b/src/include/catalog/pg_constraint.h
@@ -45,6 +45,7 @@ CATALOG(pg_constraint,2606)
 	char		contype;		/* constraint type; see codes below */
 	bool		condeferrable;	/* deferrable constraint? */
 	bool		condeferred;	/* deferred by default? */
+	bool		convalidated;	/* constraint has been validated? */
 
 	/*
 	 * conrelid and conkey are only meaningful if the constraint applies to a
@@ -148,29 +149,30 @@ typedef FormData_pg_constraint *Form_pg_constraint;
  *		compiler constants for pg_constraint
  * ----------------
  */
-#define Natts_pg_constraint					22
+#define Natts_pg_constraint					23
 #define Anum_pg_constraint_conname			1
 #define Anum_pg_constraint_connamespace		2
 #define Anum_pg_constraint_contype			3
 #define Anum_pg_constraint_condeferrable	4
 #define Anum_pg_constraint_condeferred		5
-#define Anum_pg_constraint_conrelid			6
-#define Anum_pg_constraint_contypid			7
-#define Anum_pg_constraint_conindid			8
-#define Anum_pg_constraint_confrelid		9
-#define Anum_pg_constraint_confupdtype		10
-#define Anum_pg_constraint_confdeltype		11
-#define Anum_pg_constraint_confmatchtype	12
-#define Anum_pg_constraint_conislocal		13
-#define Anum_pg_constraint_coninhcount		14
-#define Anum_pg_constraint_conkey			15
-#define Anum_pg_constraint_confkey			16
-#define Anum_pg_constraint_conpfeqop		17
-#define Anum_pg_constraint_conppeqop		18
-#define Anum_pg_constraint_conffeqop		19
-#define Anum_pg_constraint_conexclop		20
-#define Anum_pg_constraint_conbin			21
-#define Anum_pg_constraint_consrc			22
+#define Anum_pg_constraint_convalidated		6
+#define Anum_pg_constraint_conrelid			7
+#define Anum_pg_constraint_contypid			8
+#define Anum_pg_constraint_conindid			9
+#define Anum_pg_constraint_confrelid		10
+#define Anum_pg_constraint_confupdtype		11
+#define Anum_pg_constraint_confdeltype		12
+#define Anum_pg_constraint_confmatchtype	13
+#define Anum_pg_constraint_conislocal		14
+#define Anum_pg_constraint_coninhcount		15
+#define Anum_pg_constraint_conkey			16
+#define Anum_pg_constraint_confkey			17
+#define Anum_pg_constraint_conpfeqop		18
+#define Anum_pg_constraint_conppeqop		19
+#define Anum_pg_constraint_conffeqop		20
+#define Anum_pg_constraint_conexclop		21
+#define Anum_pg_constraint_conbin			22
+#define Anum_pg_constraint_consrc			23
 
 
 /* Valid values for contype */
@@ -205,6 +207,7 @@ extern Oid CreateConstraintEntry(const char *constraintName,
 					  char constraintType,
 					  bool isDeferrable,
 					  bool isDeferred,
+					  bool isValidated,
 					  Oid relId,
 					  const int16 *constraintKey,
 					  int constraintNKeys,
@@ -228,6 +231,7 @@ extern Oid CreateConstraintEntry(const char *constraintName,
 
 extern void RemoveConstraintById(Oid conId);
 extern void RenameConstraintById(Oid conId, const char *newname);
+extern void SetValidatedConstraintById(Oid conId);
 
 extern bool ConstraintNameIsUsed(ConstraintCategory conCat, Oid objId,
 					 Oid objNamespace, const char *conname);
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 3d2ae99..5714a54 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -1140,6 +1140,7 @@ typedef enum AlterTableType
 	AT_ReAddIndex,				/* internal to commands/tablecmds.c */
 	AT_AddConstraint,			/* add constraint */
 	AT_AddConstraintRecurse,	/* internal to commands/tablecmds.c */
+	AT_ValidateConstraint,		/* validate constraint */
 	AT_ProcessedConstraint,		/* pre-processed add constraint (local in
 								 * parser/parse_utilcmd.c) */
 	AT_DropConstraint,			/* drop constraint */
@@ -1181,6 +1182,7 @@ typedef struct AlterTableCmd	/* one subcommand of an ALTER TABLE */
 	Node	   *transform;		/* transformation expr for ALTER TYPE */
 	DropBehavior behavior;		/* RESTRICT or CASCADE for DROP cases */
 	bool		missing_ok;		/* skip error if missing? */
+	bool		validated;
 } AlterTableCmd;
 
 
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h
index 578d3cd..7dad001 100644
--- a/src/include/parser/kwlist.h
+++ b/src/include/parser/kwlist.h
@@ -397,6 +397,7 @@ PG_KEYWORD("user", USER, RESERVED_KEYWORD)
 PG_KEYWORD("using", USING, RESERVED_KEYWORD)
 PG_KEYWORD("vacuum", VACUUM, UNRESERVED_KEYWORD)
 PG_KEYWORD("valid", VALID, UNRESERVED_KEYWORD)
+PG_KEYWORD("validate", VALIDATE, UNRESERVED_KEYWORD)
 PG_KEYWORD("validator", VALIDATOR, UNRESERVED_KEYWORD)
 PG_KEYWORD("value", VALUE_P, UNRESERVED_KEYWORD)
 PG_KEYWORD("values", VALUES, COL_NAME_KEYWORD)
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 3d126bb..db8acff 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -184,6 +184,10 @@ DETAIL:  Key (a)=(5) is not present in table "tmp2".
 DELETE FROM tmp3 where a=5;
 -- Try (and succeed)
 ALTER TABLE tmp3 add constraint tmpconstr foreign key (a) references tmp2 match full;
+ALTER TABLE tmp3 drop constraint tmpconstr;
+-- Try NOT VALID and then VALIDATE CONSTRAINT
+ALTER TABLE tmp3 add constraint tmpconstr foreign key (a) references tmp2 match full NOT VALID;
+ALTER TABLE tmp3 validate constraint tmpconstr;
 -- Try (and fail) to create constraint from tmp5(a) to tmp4(a) - unique constraint on
 -- tmp4 is a,b
 ALTER TABLE tmp5 add constraint tmpconstr foreign key(a) references tmp4(a) match full;
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index 4895768..6aaee1a 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -221,6 +221,11 @@ DELETE FROM tmp3 where a=5;
 
 -- Try (and succeed)
 ALTER TABLE tmp3 add constraint tmpconstr foreign key (a) references tmp2 match full;
+ALTER TABLE tmp3 drop constraint tmpconstr;
+
+-- Try NOT VALID and then VALIDATE CONSTRAINT
+ALTER TABLE tmp3 add constraint tmpconstr foreign key (a) references tmp2 match full NOT VALID;
+ALTER TABLE tmp3 validate constraint tmpconstr;
 
 -- Try (and fail) to create constraint from tmp5(a) to tmp4(a) - unique constraint on
 -- tmp4 is a,b