On Tue, May 22, 2012 at 3:55 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Robert Haas <robertmh...@gmail.com> writes: >>> deik3qfhu265n6=> with hello as (select 'hello' as name) >>> deik3qfhu265n6-> , bye as (select 'bye' as name) >>> deik3qfhu265n6-> select * from hello UNION ALL select * from bye; >>> ERROR: failed to find conversion function from unknown to text > >> I think it should return a column of type text, just as if you'd done this: >> select v from (select 'hello' union all select 'bye') x(v); > > I don't think it's a great idea to make CTEs handle this differently > from other places where the same issue arises (from memory, views and > INSERT/SELECT have problems with unknown literals, and there are > probably other places I'm forgetting). > > Should we institute a uniform policy of forcing unknown sub-select > outputs to text type? This would almost certainly break a few peoples' > queries, but the reduction of surprise might be worth it for most.
I think if we can't do real type inference, forcing unknown to text is probably the least of evils. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
