Reverting previous commit, pending investigation

of sporadic seg faults from various build farm members.

doc/src/sgml/ref/alter_table.sgml

@@ -46,7 +46,6 @@ ALTER TABLE [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
     ALTER [ COLUMN ] <replaceable class="PARAMETER">column_name</replaceable> SET STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN }
     ADD <replaceable class="PARAMETER">table_constraint</replaceable> [ NOT VALID ]
     ADD <replaceable class="PARAMETER">table_constraint_using_index</replaceable>
-    ALTER CONSTRAINT <replaceable class="PARAMETER">constraint_name</replaceable> [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]
     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 ]
@@ -317,16 +316,6 @@ ALTER TABLE [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
     </listitem>
    </varlistentry>
 
-   <varlistentry>
-    <term><literal>ALTER CONSTRAINT</literal></term>
-    <listitem>
-     <para>
-      This form alters the attributes of a constraint that was previously
-      created. Currently only foreign key constraints may be altered.
-     </para>
-    </listitem>
-   </varlistentry>
-
    <varlistentry>
     <term><literal>VALIDATE CONSTRAINT</literal></term>
     <listitem>

src/backend/commands/tablecmds.c

@@ -275,8 +275,6 @@ static void AlterIndexNamespaces(Relation classRel, Relation rel,
 static void AlterSeqNamespaces(Relation classRel, Relation rel,
 				   Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved,
 				   LOCKMODE lockmode);
-static void ATExecAlterConstraint(Relation rel, AlterTableCmd *cmd,
-						 bool recurse, bool recursing, LOCKMODE lockmode);
 static void ATExecValidateConstraint(Relation rel, char *constrName,
 						 bool recurse, bool recursing, LOCKMODE lockmode);
 static int transformColumnNameList(Oid relId, List *colList,
@@ -2888,7 +2886,6 @@ AlterTableGetLockLevel(List *cmds)
 			case AT_SetOptions:
 			case AT_ResetOptions:
 			case AT_SetStorage:
-			case AT_AlterConstraint:
 			case AT_ValidateConstraint:
 				cmd_lockmode = ShareUpdateExclusiveLock;
 				break;
@@ -3127,9 +3124,6 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
 			ATPrepAddInherit(rel);
 			pass = AT_PASS_MISC;
 			break;
-		case AT_AlterConstraint:		/* ALTER CONSTRAINT */
-			ATSimplePermissions(rel, ATT_TABLE);
-			break;
 		case AT_ValidateConstraint:		/* VALIDATE CONSTRAINT */
 			ATSimplePermissions(rel, ATT_TABLE);
 			/* Recursion occurs during execution phase */
@@ -3308,9 +3302,6 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
 		case AT_AddIndexConstraint:		/* ADD CONSTRAINT USING INDEX */
 			ATExecAddIndexConstraint(tab, rel, (IndexStmt *) cmd->def, lockmode);
 			break;
-		case AT_AlterConstraint:		/* ALTER CONSTRAINT */
-			ATExecAlterConstraint(rel, cmd, false, false, lockmode);
-			break;
 		case AT_ValidateConstraint:		/* VALIDATE CONSTRAINT */
 			ATExecValidateConstraint(rel, cmd->name, false, false, lockmode);
 			break;
@@ -6182,135 +6173,6 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
 	heap_close(pkrel, NoLock);
 }
 
-/*
- * ALTER TABLE ALTER CONSTRAINT
- *
- * Update the attributes of a constraint.
- *
- * Currently only works for Foreign Key constraints.
- * Foreign keys do not inherit, so we purposely ignore the
- * recursion bit here, but we keep the API the same for when
- * other constraint types are supported.
- */
-static void
-ATExecAlterConstraint(Relation rel, AlterTableCmd *cmd,
-						 bool recurse, bool recursing, LOCKMODE lockmode)
-{
-	Relation	conrel;
-	SysScanDesc scan;
-	ScanKeyData key;
-	HeapTuple	contuple;
-	Form_pg_constraint currcon = NULL;
-	Constraint	*cmdcon = NULL;
-	bool		found = false;
-
-	Assert(IsA(cmd->def, Constraint));
-	cmdcon = (Constraint *) cmd->def;
-
-	conrel = heap_open(ConstraintRelationId, RowExclusiveLock);
-
-	/*
-	 * Find and check 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(contuple = systable_getnext(scan)))
-	{
-		currcon = (Form_pg_constraint) GETSTRUCT(contuple);
-		if (strcmp(NameStr(currcon->conname), cmdcon->conname) == 0)
-		{
-			found = true;
-			break;
-		}
-	}
-
-	if (!found)
-		ereport(ERROR,
-				(errcode(ERRCODE_UNDEFINED_OBJECT),
-				 errmsg("constraint \"%s\" of relation \"%s\" does not exist",
-						cmdcon->conname, RelationGetRelationName(rel))));
-
-	if (currcon->contype != CONSTRAINT_FOREIGN)
-		ereport(ERROR,
-				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
-				 errmsg("constraint \"%s\" of relation \"%s\" is not a foreign key constraint",
-						cmdcon->conname, RelationGetRelationName(rel))));
-
-	if (currcon->condeferrable != cmdcon->deferrable ||
-		currcon->condeferred != cmdcon->initdeferred)
-	{
-		HeapTuple	copyTuple;
-		HeapTuple	tgtuple;
-		Form_pg_constraint copy_con;
-		Form_pg_trigger copy_tg;
-		ScanKeyData tgkey;
-		SysScanDesc tgscan;
-		Relation	tgrel;
-
-		/*
-		 * Now update the catalog, while we have the door open.
-		 */
-		copyTuple = heap_copytuple(contuple);
-		copy_con = (Form_pg_constraint) GETSTRUCT(copyTuple);
-		copy_con->condeferrable = cmdcon->deferrable;
-		copy_con->condeferred = cmdcon->initdeferred;
-		simple_heap_update(conrel, &copyTuple->t_self, copyTuple);
-		CatalogUpdateIndexes(conrel, copyTuple);
-
-		InvokeObjectPostAlterHook(ConstraintRelationId,
-								  HeapTupleGetOid(contuple), 0);
-
-		heap_freetuple(copyTuple);
-
-		/*
-		 * Now we need to update the multiple entries in pg_trigger
-		 * that implement the constraint.
-		 */
-		tgrel = heap_open(TriggerRelationId, RowExclusiveLock);
-
-		ScanKeyInit(&tgkey,
-					Anum_pg_trigger_tgconstraint,
-					BTEqualStrategyNumber, F_OIDEQ,
-					ObjectIdGetDatum(HeapTupleGetOid(contuple)));
-
-		tgscan = systable_beginscan(tgrel, TriggerConstraintIndexId, true,
-									SnapshotNow, 1, &tgkey);
-
-		while (HeapTupleIsValid(tgtuple = systable_getnext(tgscan)))
-		{
-			copyTuple = heap_copytuple(tgtuple);
-			copy_tg = (Form_pg_trigger) GETSTRUCT(copyTuple);
-			copy_tg->tgdeferrable = cmdcon->deferrable;
-			copy_tg->tginitdeferred = cmdcon->initdeferred;
-			simple_heap_update(tgrel, &copyTuple->t_self, copyTuple);
-			CatalogUpdateIndexes(tgrel, copyTuple);
-
-			InvokeObjectPostAlterHook(TriggerRelationId,
-										HeapTupleGetOid(tgtuple), 0);
-
-			heap_freetuple(copyTuple);
-		}
-
-		systable_endscan(tgscan);
-
-		heap_close(tgrel, RowExclusiveLock);
-
-		/*
-		 * Invalidate relcache so that others see the new attributes.
-		 */
-		CacheInvalidateRelcache(rel);
-	}
-
-	systable_endscan(scan);
-
-	heap_close(conrel, RowExclusiveLock);
-}
-
 /*
  * ALTER TABLE VALIDATE CONSTRAINT
  *

src/backend/parser/gram.y

@@ -1941,21 +1941,6 @@ alter_table_cmd:
 					n->def = $2;
 					$$ = (Node *)n;
 				}
-			/* ALTER TABLE <name> ALTER CONSTRAINT ... */
-			| ALTER CONSTRAINT name ConstraintAttributeSpec
-				{
-					AlterTableCmd *n = makeNode(AlterTableCmd);
-					Constraint *c = makeNode(Constraint);
-					n->subtype = AT_AlterConstraint;
-					n->def = (Node *) c;
-					c->contype = CONSTR_FOREIGN; /* others not supported, yet */
-					c->conname = $3;
-					processCASbits($4, @4, "ALTER CONSTRAINT statement",
-									&c->deferrable,
-									&c->initdeferred,
-									NULL, NULL, yyscanner);
-					$$ = (Node *)n;
-				}
 			/* ALTER TABLE <name> VALIDATE CONSTRAINT ... */
 			| VALIDATE CONSTRAINT name
 				{

src/include/nodes/parsenodes.h

@@ -1209,7 +1209,6 @@ typedef enum AlterTableType
 	AT_AddConstraint,			/* add constraint */
 	AT_AddConstraintRecurse,	/* internal to commands/tablecmds.c */
 	AT_ReAddConstraint,			/* internal to commands/tablecmds.c */
-	AT_AlterConstraint,			/* alter constraint */
 	AT_ValidateConstraint,		/* validate constraint */
 	AT_ValidateConstraintRecurse,		/* internal to commands/tablecmds.c */
 	AT_ProcessedConstraint,		/* pre-processed add constraint (local in

src/test/regress/expected/foreign_key.out

@@ -1132,15 +1132,6 @@ CREATE TEMP TABLE fktable (
     id int primary key,
     fk int references pktable deferrable initially deferred
 );
--- check ALTER CONSTRAINT
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE;
--- illegal option
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE INITIALLY DEFERRED;
-ERROR:  constraint declared INITIALLY DEFERRED must be DEFERRABLE
-LINE 1: ...e ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE INITIALLY ...
-                                                             ^
--- reset
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey DEFERRABLE INITIALLY DEFERRED;
 INSERT INTO pktable VALUES (5, 10);
 BEGIN;
 -- doesn't match PK, but no error yet
@@ -1151,16 +1142,6 @@ UPDATE fktable SET id = id + 1;
 COMMIT;
 ERROR:  insert or update on table "fktable" violates foreign key constraint "fktable_fk_fkey"
 DETAIL:  Key (fk)=(20) is not present in table "pktable".
--- change the constraint definition and retest
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey DEFERRABLE INITIALLY IMMEDIATE;
-BEGIN;
--- doesn't match PK, should throw error now
-INSERT INTO fktable VALUES (0, 20);
-ERROR:  insert or update on table "fktable" violates foreign key constraint "fktable_fk_fkey"
-DETAIL:  Key (fk)=(20) is not present in table "pktable".
-COMMIT;
--- reset
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey DEFERRABLE INITIALLY DEFERRED;
 -- check same case when insert is in a different subtransaction than update
 BEGIN;
 -- doesn't match PK, but no error yet

src/test/regress/sql/foreign_key.sql

@@ -818,13 +818,6 @@ CREATE TEMP TABLE fktable (
     fk int references pktable deferrable initially deferred
 );
 
--- check ALTER CONSTRAINT
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE;
--- illegal option
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE INITIALLY DEFERRED;
--- reset
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey DEFERRABLE INITIALLY DEFERRED;
-
 INSERT INTO pktable VALUES (5, 10);
 
 BEGIN;
@@ -838,19 +831,6 @@ UPDATE fktable SET id = id + 1;
 -- should catch error from initial INSERT
 COMMIT;
 
--- change the constraint definition and retest
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey DEFERRABLE INITIALLY IMMEDIATE;
-
-BEGIN;
-
--- doesn't match PK, should throw error now
-INSERT INTO fktable VALUES (0, 20);
-
-COMMIT;
-
--- reset
-ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey DEFERRABLE INITIALLY DEFERRED;
-
 -- check same case when insert is in a different subtransaction than update
 
 BEGIN;