Could you create the table without the C column
then create a view test_view with
select a,b,a+b as c,id from test;
Oisin
Bert wrote:
> Hi list
>
> I have a table construction like the one seen below, when i am updating
> or inserting i get a recurion, logical. But how to manage it that the
> rule is just doing it one time. Or is it possible to do the sum of a
> and b in an other way?
>
> CREATE TABLE test
> (
> a int2,
> b int2,
> c int2,
> id int2 NOT NULL,
> CONSTRAINT id_test PRIMARY KEY (id)
> )
> WITHOUT OIDS;
> ALTER TABLE test OWNER TO postgres;
>
>
> CREATE OR REPLACE RULE sum_op AS
> ON INSERT TO test DO UPDATE test SET c = new.a + new.b
> WHERE test.id = new.id;
>
> CREATE OR REPLACE RULE sum_op_up AS
> ON UPDATE TO test DO UPDATE test SET c = test.a + test.b
> WHERE test.id = new.id;
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend
>