Re: [HACKERS] optimizer, again... - Mailing list pgsql-hackers

From Vadim B. Mikheev
Subject Re: [HACKERS] optimizer, again...
Date
Msg-id 7a53a9cab1765e0cafbd73ed3d63ffee
Whole thread Raw
List pgsql-hackers
Bruce Momjian wrote:
>
> >
> > Bruce Momjian wrote:
> > >
> > > I have found the following patch from Martin and have installed it in
> > > the source tree.
> > >
> > > It enables GEQO if more than six tables is used.
> > >
> > > > 4.) I vote for a standard PG optimizer/GEQO switch.
> > > >     It can be deprecated later on.
> > > >     Till 6 relation in a query: standard PG optimizer
> > > >     More than 6 relation in a query: GEQO
> > > >     Patches are included.
> > > >
> > > >
> > > > !     if ( (_use_geqo_) || length(root->base_relation_list_) >= GEQO_RELS )
> >                             ^^
> > though it's not what I suggested, I don't object...
>
> Man, Vadim is sharp.
>
> I never saw this.
>
> If GEQO is defaulting to ON, I think this should be &&?
>
> Comments?

&& would be nice in conjunction with SET geqo to 'on=XXX'.
                                                    ^^^^
If no one has time to implement it...

Vadim

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