Re: Final Patch for GROUPING SETS

On Thu, May 14, 2015 at 08:38:07AM +0200, Andres Freund wrote:
> On 2015-05-14 02:32:04 -0400, Noah Misch wrote:
> > On Thu, May 14, 2015 at 07:50:31AM +0200, Andres Freund wrote:
> > > Andrew, is that a structure you could live with, or not?
> > > 
> > > Others, what do you think?
> > 
> > Andrew and I discussed that very structure upthread:
> 
> > http://www.postgresql.org/message-id/87d26zd9k8.fsf@news-spur.riddles.org.uk
> 
> I don't really believe that that'd necesarily be true. I think if done
> like I sketched it'll likely end up being simpler than the currently
> proposed code.  I also don't see why this would make combining hashing
> and sorting any more complex than now. If anything the contrary.
> 
> > http://www.postgresql.org/message-id/20141231085845.GA2148306@tornado.leadboat.com
> > http://www.postgresql.org/message-id/20141231210553.GB2159277@tornado.leadboat.com
> > 
> > I still believe the words I wrote in my two messages cited.
> 
> I.e. that you think it's a sane approach, despite the criticism?

Yes.  I won't warrant that it proves better, but it looks promising.  Covering
hash aggregation might entail a large preparatory refactoring of nodeHash.c,
but beyond development cost I can't malign that.