Re: Quartile (etc) ranking in a SQL statement?

In a PLPGPSQL script, once you know count(*) try

execute ''select * from table limit '' || int4( theCount / 4);

If you want numbering, create a sequence and add nextval() to the query.

JLL

Jeff Boes wrote:
>
> Here's a puzzler:
>
> Given a query that returns rows ranked by some criteria, how can I write
> another query around it that will give me the (say) first quartile (top
> 25%)? Another way of putting it is: if I have rows that look like this:
>
> aaa | 1251
> aba | 1197
> cax | 1042
> ... | ...
> axq | 23
> (142 rows)
>
> How can I write a query that will return these as
>
> 1 | aaa | 1251
> 2 | aba | 1197
> 3 | cax | 1042
> ... | ... | ...
> 142 | axq | 23
>
> --
> Jeff Boes vox 616.226.9550 ext 24
> Database Engineer fax 616.349.9076
> Nexcerpt, Inc. http://www.nexcerpt.com
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