Re: LIMIT within UNION? - Mailing list pgsql-sql

>>>>> "Andrew" == Andrew Perrin <clists@perrin.socsci.unc.edu> writes:
   Andrew> What I've done is to write a script that counts the number   Andrew> of eligible exposure candidates:
   Andrew> SELECT count(*) FROM participants WHERE <eligibility>   Andrew>  AND typenr=1
   Andrew> Then subtract that number (currently 28) from 200 to get   Andrew> 172 control participants. Then the
problemstarts.
 
   [...]
   Andrew> returns ERROR:  parser: parse error at or near "ORDER"

Can you do this via a subselect:

SELECT * FROM    ( SELECT ... FROM participants     WHERE typenr=1 AND <eligibility>     UNION     SELECT ... FROM
participants    WHERE typenr=2 LIMIT 172 )
 
ORDER BY zip;

roland
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