Re: Support for idempotent schema changes?

Within the context of a script, executing:

Begin
Statement1
Statement2
Statement3
Commit

Where I only wish to commit if the error is specific to the object
already existing, and rollback for all other errors, what's the best way
to accomplish that?


-----Original Message-----
From: Peter Eisentraut [mailto:peter_e@gmx.net]
Sent: Saturday, March 03, 2007 11:45 PM
To: pgsql-general@postgresql.org
Cc: David Lowe
Subject: Re: [GENERAL] Support for idempotent schema changes?

David Lowe wrote:
> So how can I make statements of the form:

> *      alter table only customers add constraint
> a_previously_missed_constraint unique (a, b, c);
>
> *      add column points int4 not null default 0;

> idempotent?

You just ignore the error if the object already exists.

--
Peter Eisentraut
http://developer.postgresql.org/~petere/