Re: Hash partitioning.

On Tue, Jun 25, 2013 at 02:52:33PM -0700, Kevin Grittner wrote:
> Claudio Freire <klaussfreire(at)gmail(dot)com> wrote:
>
> > Did you try "select * from foo where (a % 16) = (1::int % 16)"?
>
> I did.  Using Robert's hashed partitioning table definitions:
>
> test=# explain select * from foo where a = 1 and (a % 16) = (1 % 16);
>                          QUERY PLAN                        
> ------------------------------------------------------------
>  Append  (cost=0.00..31.53 rows=2 width=36)
>    ->  Seq Scan on foo  (cost=0.00..0.00 rows=1 width=36)
>          Filter: ((a = 1) AND ((a % 16) = 1))
>    ->  Seq Scan on foo1  (cost=0.00..31.53 rows=1 width=36)
>          Filter: ((a = 1) AND ((a % 16) = 1))
> (5 rows)
>
> So if you are generating your queries through something capable of
> generating that last clause off of the first, this could work.  Not

OK, so what is it in our code that requires that? It is a type
mismatch?

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +