Re: Typmod associated with multi-row VALUES constructs

Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> Tom Lane wrote:
>> In HEAD, we could change the RTE data structure so that
>> transformValuesClause could save the typmod information in the RTE,
>> keeping the lookups cheap.

> Hmm, I think this would be useful for the XMLTABLE patch too.  I talked
> a bit about it at
> https://www.postgresql.org/message-id/20161122204730.dgipy6gxi25j4e6a@alvherre.pgsql

I dunno.  If your example there is correct that XMLTABLE can be called as
a plain function in a SELECT list, then I doubt that we want to tie
anything about it to the RTE data structure.  If anything, the case where
it appears in FROM seems to need to be treated as a generic RTE_FUNCTION
case.

I've been trying to avoid getting involved in the XMLTABLE patch, mainly
because I know zip about XML, but maybe I need to take a look.
        regards, tom lane