Re: Problem with ROWs and UNION

On Thu, May 12, 2005 at 12:32:48PM -0700, elein wrote:

> --
> -- UNION of ROWS doesn't work (simply wrong)
> --
> select ROW('4514 Cherry St','Oakland','CA','94666')::addrs
> UNION
> select ROW('4515 Cherry St','Oakland','CA','94666')::addrs;
> -- ERROR: could not identify an ordering operator for type addrs
> -- HINT: Use an explicit ordering operator or modify the query.

UNION ALL does work:

alvherre=# select ROW('4514 Cherry St','Oakland','CA','94666')::addrs
UNION ALL
select ROW('4515 Cherry St','Oakland','CA','94666')::addrs;
row
-------------------------------------
("4514 Cherry St",Oakland,CA,94666)
("4515 Cherry St",Oakland,CA,94666)
(2 filas)

I think the error message is misleading though, because the user has no
way to specify the ordering operator to UNION.

I think you could create a btree operator class to make it all work.

--
Alvaro Herrera (<alvherre[a]surnet.cl>)
"And as an added bonus, now my computer goes to the toilet for me, leaving me
free to spend time on more useful activities! yay slug codefests!" (C. Parker)