Re: Notify rule - Mailing list pgsql-general

From Merlin Moncure
Subject Re: Notify rule
Date
Msg-id AANLkTikxV2dbiKKLrtKf5D+a0J+SirLj_+ct23Bi13nn@mail.gmail.com
Whole thread Raw
In response to Notify rule  (ivan_14_32 <ivan_14_32@mail.ru>)
Responses Re: Notify rule  (Scott Ribe <scott_ribe@elevated-dev.com>)
List pgsql-general
On Tue, Feb 22, 2011 at 1:03 AM, ivan_14_32 <ivan_14_32@mail.ru> wrote:
> Hi!
> I trying to create rule for update notifing:
>
> CREATE OR REPLACE RULE "ttt_NotifyU" AS
>     ON UPDATE TO "ttt" DO
>  NOTIFY "ttt", '88';
> this work.
>
> But this
> CREATE OR REPLACE RULE "ttt_NotifyU" AS
>     ON UPDATE TO "ttt" DO
>  NOTIFY "ttt", NEW."id";
> don't (syntax error),
> NOTIFY "ttt", CAST(NEW."id" as text)
> too.
>
> Q: How can I send tuple id (integer primary key) via notify using Rule?
>     Target is erasing deprecated tuples from application's cache.

why use a rule here and not a trigger? triggers might be a bit more
verbose to right but explicit rules have and endless list of gotchas
and should be avoided unless you have a really good reason not to.

merlin

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