Re: Sorted group by

Matthew Wakeling <matthew@flymine.org> wrote:

> I'm trying to eke a little bit more performance out of an
> application

In addition to the suggestion from Thomas Kellerer, it would be
interesting to try the following and see how performance compares
using real data.

select group, value from tbl x
  where not exists
        (select * from tbl y
          where y.group = x.group and y.number > x.number);

We have a lot of code using this general technique, and I'm curious
whether there are big gains to be had by moving to the windowing
functions.  (I suspect there are.)

-Kevin