Re: Removing Functionally Dependent GROUP BY Columns

On Mon, Nov 30, 2015 at 11:00 PM, David Rowley
<david.rowley@2ndquadrant.com> wrote:
> There are in fact also two queries in TPC-H (Q10 and Q18) which are written
> to include all of the non-aggregated column in the GROUP BY list. During a
> recent test I witnessed a 50% gain in performance in Q10 by removing the
> unneeded columns from the GROUP BY clause.

Wow, that's pretty impressive.  +1 for trying to do something about this.

(Full disclosure: I have not read your patch.)

-- 
Robert Haas
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