rule with multiple DELETE action part - Mailing list pgsql-general

Hello,

now, my only question is how I can make a rule on a view with multiple delete action part which
works well. I need a mechanism which deletes two rows from two tables
which are in a one-to-one join.

The example listed below is a quite different from the real tables I use.
The table in the same role as "t_two" references the other table ("t_one").
If rules with multiple action don't work correctly this would mean that
my only last chance is using the REFERENCES constraint with ON DELETE CASCADE option?
I hope not, because it is not for the same, I want to deny to delete rows
if it has a pair in the other table.

By the way, multiple inserts seem to work.

try=# CREATE TABLE t_one (c_i integer PRIMARY KEY, c_t text);
CREATE
try=#  CREATE TABLE t_two (c_i integer REFERENCES t_one, c_d date);
CREATE
try=# CREATE VIEW v_one_two AS SELECT t_one.oid as c_oid, t_one.c_i, c_d, c_t
try-# FROM t_one, t_two WHERE t_one.c_i = t_two.c_i;
CREATE 81186 1
try=# CREATE RULE r_one_two_del AS ON DELETE TO v_one_two
try-# DO INSTEAD (DELETE FROM t_two WHERE c_i = old.c_i; DELETE FROM t_one WHERE c_i = old.c_i;);
CREATE 81187 1

try=# SELECT * FROM v_one_two;
 c_oid | c_i |    c_d     |  c_t
-------+-----+------------+-------
 81157 |   1 | 2000-09-01 | hello
 81158 |   2 | 1999-12-31 | world
 81159 |   3 | 2000-08-12 | brave
(3 rows)

try=# DELETE FROM v_one_two WHERE c_i = 2;
DELETE 0
try=# SELECT * FROM t_one;
 c_i |  c_t
-----+-------
   1 | hello
   2 | world
   3 | brave
   4 | guy
(4 rows)

try=# SELECT * FROM t_two;
 c_i |    c_d
-----+------------
   1 | 2000-09-01
   3 | 2000-08-12
(2 rows)


Papp Gyozo

s7461pap@hszk.bme.hu, gerzson17@freemail.hu