Richard --
You might post the results of "EXPLAIN ANALYZE <your SQL here>;" ... be sure to run it in a transaction if you want to
beable roll it back. Perhaps try "EXPLAIN <your SQL>;" first as it is faster, but EXPLAIN ANALYZE shows what the
planneris doing.
You wrote:
>
> P.S. Sometimes, some queries seem to benefit from being cancelled and then immediately
> re-started. As there are being run in a transaction, I can't see how this could make a difference.
> Am I missing anything obvious? Occasionally, a re-start of postgresql-8.4l itself seems to help.
This may be the result of caching of the desired rows, either by PostgreSQL or by your operating system. The rollback
wouldn'teffect this -- the rows are already in memory and not on disk waiting to be grabbed -- much faster on all
subsequentqueries.
HTH,
Greg Williamson
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