Re: LIMIT and UNION ALL - Mailing list pgsql-performance

From Tom Lane
Subject Re: LIMIT and UNION ALL
Date
Msg-id 25771.1306429243@sss.pgh.pa.us
Whole thread Raw
In response to Re: LIMIT and UNION ALL  (Dave Johansen <davejohansen@gmail.com>)
List pgsql-performance
Dave Johansen <davejohansen@gmail.com> writes:
> ...  So is there a way to make the
> planner perform the same sort of operation and push those same constraints
> into the sub-queries on its own?

No.  As was mentioned upthread, there is a solution for this in 9.1,
although it doesn't work in exactly the way you suggest.

            regards, tom lane

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