Fix for possible referential integrity violation when a qualified ON INSERT

rule split the query into one INSERT and one UPDATE where the UPDATE
then hit's the just created row without modifying the key fields again.
In this special case, the new key slipped in totally unchecked.

Jan

src/backend/utils/adt/ri_triggers.c

@@ -17,7 +17,7 @@
  *
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  *
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/ri_triggers.c,v 1.62 2003/10/06 16:38:28 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/ri_triggers.c,v 1.63 2003/10/31 03:58:20 wieck Exp $
  *
  * ----------
  */
@@ -379,7 +379,9 @@ RI_FKey_check(PG_FUNCTION_ARGS)
 	 */
 	if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
 	{
-		if (ri_KeysEqual(fk_rel, old_row, new_row, &qkey,
+		if (HeapTupleHeaderGetXmin(old_row->t_data) !=
+				GetCurrentTransactionId() &&
+				ri_KeysEqual(fk_rel, old_row, new_row, &qkey,
 						 RI_KEYPAIR_FK_IDX))
 		{
 			heap_close(pk_rel, RowShareLock);

src/test/regress/expected/foreign_key.out

@@ -1029,3 +1029,62 @@ INSERT INTO fktable VALUES (100, 200);
 COMMIT;
 ERROR:  insert or update on table "fktable" violates foreign key constraint "$1"
 DETAIL:  Key (fk)=(200) is not present in table "pktable".
+-- Check that rewrite rules splitting one INSERT into multiple
+-- conditional statements does not disable FK checking.
+create table rule_and_refint_t1 (
+	id1a integer,
+	id1b integer,
+	
+	primary key (id1a, id1b)
+);
+NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "rule_and_refint_t1_pkey" for table "rule_and_refint_t1"
+create table rule_and_refint_t2 (
+	id2a integer,
+	id2c integer,
+	
+	primary key (id2a, id2c)
+);
+NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "rule_and_refint_t2_pkey" for table "rule_and_refint_t2"
+create table rule_and_refint_t3 (
+	id3a integer,
+	id3b integer,
+	id3c integer,
+	data text,
+	primary key (id3a, id3b, id3c),
+	foreign key (id3a, id3b) references rule_and_refint_t1 (id1a, id1b),
+	foreign key (id3a, id3c) references rule_and_refint_t2 (id2a, id2c)
+);
+NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "rule_and_refint_t3_pkey" for table "rule_and_refint_t3"
+insert into rule_and_refint_t1 values (1, 11);
+insert into rule_and_refint_t1 values (1, 12);
+insert into rule_and_refint_t1 values (2, 21);
+insert into rule_and_refint_t1 values (2, 22);
+insert into rule_and_refint_t2 values (1, 11);
+insert into rule_and_refint_t2 values (1, 12);
+insert into rule_and_refint_t2 values (2, 21);
+insert into rule_and_refint_t2 values (2, 22);
+insert into rule_and_refint_t3 values (1, 11, 11, 'row1');
+insert into rule_and_refint_t3 values (1, 11, 12, 'row2');
+insert into rule_and_refint_t3 values (1, 12, 11, 'row3');
+insert into rule_and_refint_t3 values (1, 12, 12, 'row4');
+insert into rule_and_refint_t3 values (1, 11, 13, 'row5');
+ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "$2"
+DETAIL:  Key (id3a,id3c)=(1,13) is not present in table "rule_and_refint_t2".
+insert into rule_and_refint_t3 values (1, 13, 11, 'row6');
+ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "$1"
+DETAIL:  Key (id3a,id3b)=(1,13) is not present in table "rule_and_refint_t1".
+create rule rule_and_refint_t3_ins as on insert to rule_and_refint_t3
+	where (exists (select 1 from rule_and_refint_t3
+			where (((rule_and_refint_t3.id3a = new.id3a)
+			and (rule_and_refint_t3.id3b = new.id3b))
+			and (rule_and_refint_t3.id3c = new.id3c))))
+	do instead update rule_and_refint_t3 set data = new.data
+	where (((rule_and_refint_t3.id3a = new.id3a)
+	and (rule_and_refint_t3.id3b = new.id3b))
+	and (rule_and_refint_t3.id3c = new.id3c));
+insert into rule_and_refint_t3 values (1, 11, 13, 'row7');
+ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "$2"
+DETAIL:  Key (id3a,id3c)=(1,13) is not present in table "rule_and_refint_t2".
+insert into rule_and_refint_t3 values (1, 13, 11, 'row8');
+ERROR:  insert or update on table "rule_and_refint_t3" violates foreign key constraint "$1"
+DETAIL:  Key (id3a,id3b)=(1,13) is not present in table "rule_and_refint_t1".

src/test/regress/sql/foreign_key.sql

@@ -694,3 +694,61 @@ INSERT INTO fktable VALUES (100, 200);
 -- error here on commit
 COMMIT;
 
+-- Check that rewrite rules splitting one INSERT into multiple
+-- conditional statements does not disable FK checking.
+create table rule_and_refint_t1 (
+	id1a integer,
+	id1b integer,
+	
+	primary key (id1a, id1b)
+);
+
+create table rule_and_refint_t2 (
+	id2a integer,
+	id2c integer,
+	
+	primary key (id2a, id2c)
+);
+
+create table rule_and_refint_t3 (
+	id3a integer,
+	id3b integer,
+	id3c integer,
+	data text,
+
+	primary key (id3a, id3b, id3c),
+
+	foreign key (id3a, id3b) references rule_and_refint_t1 (id1a, id1b),
+	foreign key (id3a, id3c) references rule_and_refint_t2 (id2a, id2c)
+);
+
+
+insert into rule_and_refint_t1 values (1, 11);
+insert into rule_and_refint_t1 values (1, 12);
+insert into rule_and_refint_t1 values (2, 21);
+insert into rule_and_refint_t1 values (2, 22);
+
+insert into rule_and_refint_t2 values (1, 11);
+insert into rule_and_refint_t2 values (1, 12);
+insert into rule_and_refint_t2 values (2, 21);
+insert into rule_and_refint_t2 values (2, 22);
+
+insert into rule_and_refint_t3 values (1, 11, 11, 'row1');
+insert into rule_and_refint_t3 values (1, 11, 12, 'row2');
+insert into rule_and_refint_t3 values (1, 12, 11, 'row3');
+insert into rule_and_refint_t3 values (1, 12, 12, 'row4');
+insert into rule_and_refint_t3 values (1, 11, 13, 'row5');
+insert into rule_and_refint_t3 values (1, 13, 11, 'row6');
+
+create rule rule_and_refint_t3_ins as on insert to rule_and_refint_t3
+	where (exists (select 1 from rule_and_refint_t3
+			where (((rule_and_refint_t3.id3a = new.id3a)
+			and (rule_and_refint_t3.id3b = new.id3b))
+			and (rule_and_refint_t3.id3c = new.id3c))))
+	do instead update rule_and_refint_t3 set data = new.data
+	where (((rule_and_refint_t3.id3a = new.id3a)
+	and (rule_and_refint_t3.id3b = new.id3b))
+	and (rule_and_refint_t3.id3c = new.id3c));
+
+insert into rule_and_refint_t3 values (1, 11, 13, 'row7');
+insert into rule_and_refint_t3 values (1, 13, 11, 'row8');