On Tuesday, June 2, 2015, <digoal@126.com> wrote:
> The following bug has been logged on the website:
>
> Bug reference: 13391
> Logged by: digoal
> Email address: digoal@126.com <javascript:;>
> PostgreSQL version: 9.4.2
> Operating system: CentOS 6.x x64
> Description:
>
> when use in/= & subquery, non exists column can elected.
> for exp:
>
> postgres=# explain (analyze,verbose) select * from table1 where c1 =
> (select
> c1 from table2 limit 1);
>
>
This is a correlated subquery, not a bug.
David J.