Thread: Rules not executed on child tables

Hi,

I noticed that when an action is executed on a parent table, rules for that=
 action that are defined on its child tables are ignored.

Example:

create table A (ind integer);
create table B () inherits (A);

CREATE OR REPLACE RULE B_delete_rule AS
    ON DELETE TO B DO INSTEAD NOTHING;

insert into B values(0);

delete from B;
-- Query returned successfully: 0 rows affected, 0 ms execution time.
-- This is what I expected

delete from A;
-- Query returned successfully: 1 row affected, 0 ms execution time.
-- This is NOT what I expected!

I am using PostgreSQL 8.4.1 on Windows XP Pro

On Wed, Aug 18, 2010 at 5:36 AM,  <depstein@alliedtesting.com> wrote:
> I noticed that when an action is executed on a parent table, rules for that
> action that are defined on its child tables are ignored.

I think this is actually design behavior.  It's really hard to use
rules for anything useful (other than views); you might want to look
at triggers instead.  Rules are basically a crude query-rewrite
system.  The rule rewriting process doesn't understand anything about
what your query is actually trying to do; it's just analyzing the
syntax (where, of course, the child tables aren't mentioned).

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company