| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Joseph Shraibman <jks(at)selectacast(dot)net> |
| Cc: | pgsql-general(at)postgresql(dot)org |
| Subject: | Re: selecting random rows |
| Date: | 2003-09-12 01:34:19 |
| Message-ID: | 4526.1063330459@sss.pgh.pa.us |
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| Lists: | pgsql-general |
Joseph Shraibman <jks(at)selectacast(dot)net> writes:
> Is there a way to get random rows besides ORDER BY random()?
Are you willing to expend an extra column in the table, plus an index on
the column, to make this fast? Then you can do it --- see discussion
just a few days ago.
http://archives.postgresql.org/pgsql-performance/2003-08/msg00526.php
If you are willing to settle for "only approximately random", you might
be able to use the primary key as a pseudo-random value. Again, see
prior discussion.
regards, tom lane
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