Re: Updating column on row update

2009/11/22 Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>

> > Thanks Scott. It's a shame a function has to be used because it then has
> > the dependency of plpgsql being loaded. I'm attempting to write a
> database
> > schema to accompany a PostgreSQL driver for a popular CMS, but I guess I
> > could get it to load plpgsql in as a language.
> > The problem now is if the the schema creation script is run against a
> > database where the language is already installed, I would get an error
> > saying it already exists. Is there a way to get it to check for it
> first,
> > and only create it if it isn't exist? Bear in mind I'd want this to be
> > compatible at least as far back as 8.1.
>
> Try this:
>
> select * from pg_language ;
>
> Pretty sure that exists pretty far back.
>

Yes, I noticed that existed in the catalogs, but how could that be
incorporated into an installation SQL script? The language constructs I
imagine I'd need to test that are in plpgsql itself.

Thanks

Thom