Re: pg_upgrade issues

Alvaro Herrera <alvherre@commandprompt.com> writes:
> Excerpts from depstein's message of lun jul 26 08:05:24 -0400 2010:
>> I just want to note that one reason regclass may be used in user tables (as opposed to, say, regtype) is that in
PL/pgSQLtrigger procedures there is a special variable TG_RELID, which provides a convenient reference to the table
thatpulled the trigger (this is the case for some of our uses). 

> I've wanted to use regclass (and regproc too, for that matter) in some
> db designs, but I've refrained precisely because of the movability issues.

> Note that you can use TG_SCHEMANAME and TG_RELNAME in plpgsql triggers
> anyway.

How does TG_RELID lead to wanting to store regclass columns, exactly?
I've always supposed that was a legacy parameter rather than something
anyone would actually use.

            regards, tom lane