Re: Is this query possible in PostgreSQL ?

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.

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