Re: [HACKERS] union and LIMIT problem

> Bruce Momjian wrote:
>
> >
> > > Does anybody know how to use UNION and LIMIT together ?
> > > I want to get 10 rows from publications and 10 rows
> > > from keys.
> > >
> > > select msg_id from publications limit 10 union
> > > select key_id from keys limit 10
> > > produces
> > > ERROR: parser: parse error at or near "union
> > >
> > > select msg_id from publications union
> > > select key_id from keys limit 10
> > > produces something I wasn't expected
> >
> > I have on the TODO list:
> >
> > * UNION with LIMIT fails
>
> and must fail by it's implementation. LIMIT is handled by the
> outermost executor loop, suppressing OFFSET result tuples and
> stopping execution after LIMIT results sent to the client.

Ah, but it works sometimes:

test=> select * from pg_language union select * from pg_language limit 1;
lanname|lanispl|lanpltrusted|lanplcallfoid|lancompiler
-------+-------+------------+-------------+-----------
|t |f |f | 0|/bin/cc
(1 row)

so we would need to get it working, or disable it from happening.

--
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