From: | Jeff Eckermann <jeff_eckermann(at)yahoo(dot)com> |
---|---|
To: | andrew_perrin(at)unc(dot)edu, Doug McNaught <doug(at)wireboard(dot)com> |
Cc: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: Performance tips |
Date: | 2002-01-10 15:04:24 |
Message-ID: | 20020110150424.42798.qmail@web20810.mail.yahoo.com |
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Thread: | |
Lists: | pgsql-general |
One way to improve performance with queries like yours
is to select the subquery results into a temporary
table, and join against that (perhaps with an index
created on the temp table, if you get a lot of rows).
Ugly and messy, but can result in massive performance
improvements on a system with limited resources, even
compared with the "EXISTS" solution.
--- Andrew Perrin <andrew_perrin(at)unc(dot)edu> wrote:
> Never mind - while I was writing the last message
> the vacuum analyze
> ended. No messages from vacuum analyze (just the
> VACUUM
> acknowledgement). I'm recreating the one
> user-created index (the rest are
> based on serials) now and will re-test queries.
>
> Thanks for everyone's help.
>
>
----------------------------------------------------------------------
> Andrew J Perrin - andrew_perrin(at)unc(dot)edu -
> http://www.unc.edu/~aperrin
> Assistant Professor of Sociology, U of North
> Carolina, Chapel Hill
> 269 Hamilton Hall, CB#3210, Chapel Hill, NC
> 27599-3210 USA
>
>
>
>
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