Excerpts from Tom Lane's message of mié nov 17 12:20:06 -0300 2010: > Alvaro Herrera <alvhe...@alvh.no-ip.org> writes: > > A customer of ours (Enova Financial) requested the ability to describe > > objects in pg_depend. The wiki contains a simplistic SQL snippet that > > does the task, but only for some of the object types, and it's rather > > ugly. It struck me that we could fulfill this very easily by exposing > > the getObjectDescription() function at the SQL level, as in the attached > > module. > > What's the point of the InvalidOid check? It seems like you're mostly > just introducing a corner case: sometimes, but not always, the function > will return NULL instead of failing for bad input. I think it should > just fail always.
If the check is not there, the calling query will have to prevent the function from being called on rows having OID=0 in pg_depend. (These rows show up in the catalog for pinned objects). The query becomes either incomplete (because you don't report pinned objects) or awkward (because you have to insert a CASE expression to avoid calling the function in that case). I don't think it's all that necessary anyway. If the function goes in without that check, it will still be a huge improvement over the statu quo. -- Álvaro Herrera <alvhe...@commandprompt.com> The PostgreSQL Company - Command Prompt, Inc. PostgreSQL Replication, Consulting, Custom Development, 24x7 support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
