Re: Filtered Query on nth row

From: Jesper Søndergaard <jsoender_at_NOSPAM.dk.oracle.com>
Date: 1998/02/06
Message-ID: <34DAE94C.A516391D@NOSPAM.dk.oracle.com>#1/1

Jeff Jackson wrote:

> Does anyone know how to do a query and filter every nth row ?
> Example,
> I have 100 rows returned but I am only intereseted in every other fith
>
> row for example.... row1, row6, row11,row16 etc.... I don't want to
> see
> rows 2,3,4,5,7,8,9,10 etc ... Is this possible ?
>
> Does SQL allow me to do this ? I have tried all kinds of queries,
> correlated, inner joins, sub queries and various expressions.

Try to use the ROWNUM column combined with an inline view:

select b.empno
from
(
select empno, mod(rownum,5) xx from emp
) a,
emp b
where a.xx = 1
and b.empno = a.empno;

/Jesper

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|
|
|                            Jesper
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|                            Technical
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         The statements and opinions expressed here are my own and
         do not necessarily represent those of Oracle Corporation.

Received on Fri Feb 06 1998 - 00:00:00 CST