Re: Query only slow on first run - Mailing list pgsql-performance

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Subject Re: Query only slow on first run
Date
Msg-id 474DDA8F.3070801@amossen.dk
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In response to Re: Query only slow on first run  ("Steinar H. Gunderson" <sgunderson@bigfoot.com>)
Responses Re: Query only slow on first run  (Jean-David Beyer <jeandavid8@verizon.net>)
Re: Query only slow on first run  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: Query only slow on first run  ("Scott Marlowe" <scott.marlowe@gmail.com>)
List pgsql-performance
> The indexes don't contain visibility information, so Postgres has to look up
> the row on disk to verify it isn't dead.

I guess this fact drastically decreases the performance. :-(
The number of rows with a random_number will just grow over time while
the number of questions with status = 1 will always be somewhat constant
at about 10.000 or most likely much less.

I could really use any kind of suggestion on how to improve the query in
order to make it scale better for large data sets The 6-7000 ms for a
clean run is really a showstopper. Need to get it below 70 ms somehow.

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