On Fri, Jul 19, 2013 at 7:47 AM, guxiaobo1982 <guxiaobo1...@qq.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?
