Re: help on SQL

test=# create table data (data int);
CREATE
test=# insert into data values(1);
INSERT 3531768 1
test=# insert into data values(2);
INSERT 3531769 1
test=# insert into data values(3);
INSERT 3531770 1
test=# insert into data values(4);
INSERT 3531771 1
test=# insert into data values(5);
INSERT 3531772 1
test=# insert into data values(6);
INSERT 3531773 1
test=# insert into data values(7);
INSERT 3531774 1
test=# select * from data where (data - 1) % 3 = 0;
data
------
1
4
7
(3 rows)

test=#

HTH

Michael

Web Applications Developer
Open World Ltd, 11 Riverside Court, Riverside Road, Bath, BA2 3DZ.
Tel: +44 1225 444950 Fax: +44 1225 336738 http://www.openworld.co.uk/

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On Wed, 21 Apr 2004, Kenneth Suralta wrote:

> hi gergely,
>
> thanks for replying..
> what i mean is supposing there is a table with the following rows:
>
> data
> -----
> 1
> 2
> 3
> 4
> 5
> 6
> 7
>
> is it possible to get every other N-row in the table?
> example, if N is 3.
> data
> -----
> 1
> 4
> 7
>
> thanks,
> kenneth
>
>
>
> Gergely Czuczy wrote:
>
> On Wed, 21 Apr 2004, Kenneth Suralta wrote:
>
>
>
> hello everyone,
>
> is it possible to get every other row in the table?
> like for example:
> data
> -----
> 1
> 2
> 3
> 4
> 5
> 6
> 7
>
>
> SELECT t.fields FROM table t WHERE data NOT IN (SELECT t2.data FROM table
> t2 WHERE some_whereclause);
>
> it will select these rows which ones are not in the subquery. but you can
> do it simply by getting the negate of the whereclause...
>
>
> Is it possible to have this result (interval of 3)?
>
> result
> ------
> 1
> 4
> 7
>
>
> i don't see what you mean. please describe it.
>
>
> thanks,
> kenneth
>
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>
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