On Fri, Jul 19, 2013 at 7:47 AM, guxiaobo1982 <guxiaobo1982(at)qq(dot)com> wrote:
> There is another situation,
>
> We have a demo table with about 17000000 rows, the "select count(1) from
> demotable" statement finishes with-in 3 seconds when executed directlly
> against the Greenplum database,but it takes about 230 seconds to finish
> when executed via postgres_fdw inside PostgreSQL 9.3 beta2, I guess that it
> may because of postgres_fdw pulling data to the PostgreSQL instance and
> counts the rows there, but I think the query optimizer should pass through
> the count() function to the Greenplum end, and gets only the result back.
>
Are you able to create a function in Greenplum which is a wrapper around
that count(*) and call that via the postgres_fdw?