Re: LIMIT within UNION?

Thanks! That did it.

The inner parens are necessary - without them the ORDER BY seems to be
parsed as part of the second subquery and is therefore a syntax error.

Best,
Andy

----------------------------------------------------------------------
Andrew J Perrin - http://www.unc.edu/~aperrin
Assistant Professor of Sociology, U of North Carolina, Chapel Hill
clists@perrin.socsci.unc.edu * andrew_perrin (at) unc.edu


On Thu, 12 Sep 2002, Tom Lane wrote:

> Andrew Perrin <clists@perrin.socsci.unc.edu> writes:
> > SELECT ... FROM participants
> > WHERE typenr=1 AND <eligibility>
> > UNION
> > SELECT ... FROM participants
> > WHERE typenr=2 LIMIT 172
> > ORDER BY zip;
> 
> I think you need
> 
> SELECT * FROM
> (
> SELECT ... FROM participants
> WHERE typenr=1 AND <eligibility>
> UNION
> (SELECT ... FROM participants
> WHERE typenr=2 LIMIT 172)
> ) ss
> ORDER BY zip;
> 
> Not sure if the inner set of parens is essential, but it might be.
> The outer SELECT superstructure is definitely necessary to give a
> place to hang the ORDER BY on.
> 
>             regards, tom lane
>