Re: CUBE, ROLLUP, GROUPING SETS?

Christopher Browne wrote:
> Centuries ago, Nostradamus foresaw when nicolas(dot)barbier(at)gmail(dot)com ("Nicolas Barbier") would write:
> > 2006/10/28, Robert Treat <xzilla(at)users(dot)sourceforge(dot)net>:
> >
> >> On Tuesday 10 October 2006 15:19, stig erikson wrote:
> >>
> >>> Are there any plans to implement CUBE, ROLLUP and/or GROUPING SETS in
> >>> future PostgreSQL versions? I could not find any info on the TODO-page.
> >>
> >> I've heard people mention it, but no one has ever come up with a
> >> solid proposal or patch. Depending on what your doing there are
> >> ways to simulate those things with more standard sql.
> >
> > CUBE, ROLLUP and GROUPING SETS are at least part of SQL 2003.
> > Supporting them would probably also include optimized ways to
> > execute them, like calculating all aggregations in one run for
> > ROLLUP (instead of doing multiple scans).
>
> I'm sure a good implementation would include such things.
>
> I'm not sure it's anywhere near trivial to do so; it may be nontrivial
> to efficiently do all those aggregates at once. We'll presumably
> discover this if and when someone begins work on it...

Our TODO has:

* Add ROLLUP, CUBE, GROUPING SETS options to GROUP BY

--
Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +