From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Jelle Ouwerkerk <jelle@openface.ca>
Cc: pgsql-sql@postgresql.org
Subject: Re: random
Date: Mon, 5 Mar 2001 16:29:12 -0500 (EST)
Message-ID: <200103052129.QAA03712@candle.pha.pa.us> (raw)
In-Reply-To: <20854.983827417@sss.pgh.pa.us>
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> >> Jelle Ouwerkerk <jelle@openface.ca> writes:
> > Also, is there a way to randomize the order of a result set?
> >>
> >> There's always
> >> SELECT * FROM foo ORDER BY random();
>
> > However:
> > test=> select * from pg_class order by random();
> > does return some output. Is it random, and if so, how?
>
> Sure. The function is marked noncachable, so it gets evaluated
> afresh at each row --- but only once per row, as the sort step doesn't
> recompute any values. Should work just peachy, and it seems to do
> so in a couple quick tests.
But random returns a random value from 0-1, right? How does that work
in ORDER BY?
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026
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To: pgsql-sql@postgresql.org
Cc: pgman@candle.pha.pa.us, tgl@sss.pgh.pa.us, jelle@openface.ca
Subject: Re: random
In-Reply-To: <200103052129.QAA03712@candle.pha.pa.us>
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