Re: [HACKERS] update_pg_pwd trigger does not work very well

> [Charset ISO-8859-1 unsupported, filtering to ASCII...]
> > Tom Lane writes:
> >
> > > 1. Since the trigger is executed as soon as a tuple is inserted/
> > > updated/deleted, it will write pg_pwd before the transaction is
> > > committed.  If you then abort the transaction, pg_pwd contains wrong
> > > data.
> >
> > Wow, that implies that every trigger that contains non-database
> > side-effects is potentially bogus. That never occured to me. Perhaps (as a
> > future plan), it would be a good idea to have deferred triggers as well?
> > Now that I think of it, wasn't that the very reason Jan had to invent the
> > separate constraint triggers?
>
> Yes!  I remember him talking about this.  I bet you can just modify your
> trigger to be of that type.

    He  could make the trigger look like a by default deferred RI
    trigger in pg_trigger, of course. Then it will  go  onto  the
    queue.

    But as soon as someone does

        SET CONSTRAINTS ALL IMMEDIATE;

    it  will be fired if queued or as soon as it appears. So it's
    not the final solution.


Jan

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