Re: random - Mailing list pgsql-sql

From Bruce Momjian
Subject Re: random
Date
Msg-id 200103052104.QAA01988@candle.pha.pa.us
Whole thread Raw
In response to Re: random  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: random  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: random  (Stephan Szabo <sszabo@megazone23.bigpanda.com>)
List pgsql-sql
> 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();
> 

How does that work?
test=> select random();      random       ------------------- 0.896045367650709(1 row)

However:test=> select * from pg_class order by random();

does return some output.  Is it random, and if so, how?

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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