Re: 8.4, One-Time Filter and subquery ( ... FROM function() union all ... )

Tom Lane <tgl@sss.pgh.pa.us> writes:

> Sergey Burladyan <eshkinkot@gmail.com> writes:
> > Oh, now problem with simple query:
> 
> > 8.4.0 from Debian
> > explain analyze select i from t where i >= 10 and i = 1;
> >                                      QUERY PLAN
> > ------------------------------------------------------------------------------------
> >  Result  (cost=0.00..0.01 rows=1 width=0) (actual time=0.002..0.002 rows=0 loops=1)
> >    One-Time Filter: false
> >  Total runtime: 0.030 ms
> 
> > CVS HEAD
> > explain analyze select i from t where i >= 10 and i = 1;
> >                                             QUERY PLAN
> > ---------------------------------------------------------------------------------------------------
> >  Seq Scan on t  (cost=0.00..17030.00 rows=1 width=4) (actual time=449.651..449.651 rows=0 loops=1)
> >    Filter: ((i >= 10) AND (i = 1))
> >  Total runtime: 449.726 ms

> Hmm, that's got nothing to do with my recent patch, because there's no
> appendrel anywhere.  Are you sure you are using the same
> constraint_exclusion setting in both cases?

Oops, of course you are right, i have constraint_exclusion = on in Debian, but
constraint_exclusion = partition by default in CVS HEAD %)

Thanks for help, Tom !

-- 
Sergey Burladyan