Re: Is this query possible in PostgreSQL ?

From: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
To: Ben-Nes Michael <miki(at)canaan(dot)co(dot)il>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Is this query possible in PostgreSQL ?
Date: 2002-07-29 03:25:50
Message-ID: 200207290325.g6T3PoR27735@candle.pha.pa.us
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Ben-Nes Michael wrote:
> Hi All
>
> While reading some SQL books i crossed on SUBSETS querry, but it seems
> postgres dont understand them.
>
> Is there another way to do this in postgres ?
> if so, where i can read about it ?
>
> SELECT * from some_table WHERE MOD(some_row, :n) = 0;

So this allows you to get every Xth result, like every 3rd row. Wow,
that is interesting. We don't have a ROWNUM like Oracle has, but if we
did you could just use mod on that:

ROWNUM % 3 = 0

You could use a cursor and fetch only every Xth row. Not sure what else
I can suggest.

--
Bruce Momjian | http://candle.pha.pa.us
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