From: Bruno Wolff III <bruno@wolff.to>
To: Enver ALTIN <enver.altin@frontsite.com.tr>
Cc: pgsql-sql@postgresql.org
Subject: Re: randomized order in select?
Date: Wed, 10 Mar 2004 13:02:50 -0600
Message-ID: <20040310190250.GA6629@wolff.to> (raw)
In-Reply-To: <1078937297.29628.12.camel@enver.office.frontsite.com.tr>
References: <1078937297.29628.12.camel@enver.office.frontsite.com.tr>
On Wed, Mar 10, 2004 at 18:48:17 +0200,
Enver ALTIN <enver.altin@frontsite.com.tr> wrote:
>
> collect an ID list, choose one randomly and retrieve it. I wish I could
> do something like:
>
> select tiptext from tips order by random limit 1
>
> in PostgreSQL.
You can but it won't be very efficient (for large tables) as it will generate
a random ordering for the whole table, probably do a sort and then return the
first record. The only thing different you need to do is add () after random:
select tiptext from tips order by random() limit 1
If the number of tips isn't very large doing the above is probably best.
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To: pgsql-sql@postgresql.org
Cc: bruno@wolff.to, enver.altin@frontsite.com.tr
Subject: Re: randomized order in select?
In-Reply-To: <20040310190250.GA6629@wolff.to>
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