Thread: conditionally executing migration code

I'm using some simple migration code to execute individual fragments of
SQL code based on the version of the schema. Is there a way to perform
an ALTER TABLE conditionally?

Example:

I want to add column foo to table bar, but only if column foo does not
exist already.

I'm trying to avoid such situations, but it's not always easy.

Thanks,
Mike
--
Michael P. Soulier <michael_soulier@mitel.com>, 613-592-2122 x2522
"Any intelligent fool can make things bigger and more complex... It
takes a touch of genius - and a lot of courage to move in the opposite
direction." --Albert Einstein

Can't you just try to add the column and catch the error?  If you're
in a transaction use a user defined function to run it an catch the
exception in pl/pgsql.

On Thu, Jun 5, 2008 at 12:15 PM, Michael P. Soulier
<michael_soulier@mitel.com> wrote:
> I'm using some simple migration code to execute individual fragments of SQL
> code based on the version of the schema. Is there a way to perform an ALTER
> TABLE conditionally?
>
> Example:
>
> I want to add column foo to table bar, but only if column foo does not exist
> already.
>
> I'm trying to avoid such situations, but it's not always easy.
>
> Thanks,
> Mike
> --
> Michael P. Soulier <michael_soulier@mitel.com>, 613-592-2122 x2522
> "Any intelligent fool can make things bigger and more complex... It
> takes a touch of genius - and a lot of courage to move in the opposite
> direction." --Albert Einstein
>
> --
> Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
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