Re: Usability tweaks for extension commands

On Feb 15, 2011, at 5:18 PM, Tom Lane wrote:

> Currently, ALTER EXTENSION UPDATE throws an error if there's nothing to
> do:
> 
> regression=# create extension adminpack ;
> CREATE EXTENSION
> regression=# alter extension adminpack update;
> ERROR:  version to install or update to must be different from old version
> 
> On reflection it seems like this is overly paranoid, and it'd be more
> useful if the ALTER just reported a NOTICE along the lines of "version
> so-and-so is already installed".  Any objections?

Makes sense to me.

> Another thought is that it'd probably be useful for there to be a
> "CREATE OR REPLACE EXTENSION" syntax, with the behavior of "install the
> extension if it's not present, else make sure it's of the specified or
> default version"; this behavior parallels CREATE OR REPLACE LANGUAGE
> which is something we've been refining for awhile.  I am not however
> entirely sure what to do with the SCHEMA option if the extension already
> exists --- we might be able to do SET SCHEMA, but perhaps that's too
> aggressive.

This one is a bit over my head, alas.

David