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

Sergey Burladyan <eshkinkot(at)gmail(dot)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?

regards, tom lane