Re: [SQL] rewriting values with before trigger

I'm by no means an expert in this, but maybe this idea would work in your
rule?

Write a function that takes text as it's input and returns either a
timestamp or NULL and then do something like:
return_timestamp(mydate::text)

This way, a valid date will be converted to it's text equiv.  You can then
use the function to look for '' and if true, return NULL and if false cast
the text string back into a timestamp or whatever and return it.

Of course, I don't know if a function that is set to return a timestamp can
even return NULL.  That might cause an error by itself.

--
Matthew Nuzum
www.bearfruit.org
cobalt@bearfruit.org

> -----Original Message-----
> From: pgsql-sql-owner@postgresql.org [mailto:pgsql-sql-
> owner@postgresql.org] On Behalf Of Robert Treat
> Sent: Thursday, April 24, 2003 3:49 PM
> To: gearond@cvc.net
> Cc: Josh Berkus; pgsql-general@postgresql.org; pgsql-sql@postgresql.org
> Subject: Re: [GENERAL] [SQL] rewriting values with before trigger
>
> On Thu, 2003-04-24 at 15:35, Dennis Gearon wrote:
> > Well,
> >     does ''::INT do anything valuable?
>
>     not in 7.3+, and given my original problem involves timestamps, not
> in
> 7.2 either.
>
> >     change column to a string, convert to INTS on the way out, STRINGS
> on the way in?
> >     use an external language to make transitions.
> >
>
> yeah, I've thought of some other crazy ways to get around this, but the
> problem is due to a bug in the application side. I was hoping I could
> write a quick hack (like adding a rule/trigger) to get around this until
> the app was fixed, but I'm not going to make my side a kludge when it
> isn't one now.
>
>
> Robert Treat
>
>
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