Re: hint unique result fro union

> Mainly, thinking about partitions, I'd like to create a small, frequently
> accessed partition and a big, rarely accessed partition.
>
> I'd like to hint pg to stop the query on the parent partition at the first
> found item (and so hint not to analyze all the childs), because I know the
> index I'm using is unique.
>

what you want is know as "Constraint Exclusion"
http://www.postgresql.org/docs/8.1/static/ddl-partitioning.html#DDL-PARTITIONING-CONSTRAINT-EXCLUSION

--
regards,
Jaime Casanova

"Programming today is a race between software engineers striving to
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