> > > Yeah, it's not expected that that's going to cost much. I am suspicious > that what you are looking at is mostly measurement overhead: during > EXPLAIN ANALYZE, each plan node has to do two gettimeofday() calls per > call, and there are lots of platforms where that is significant relative > to the actual work done per node. > > You might try comparing the overall times for select count(*) from ... > rather than EXPLAIN ANALYZE for these two cases. If those times are > much closer together than what you're getting from EXPLAIN ANALYZE, > then you've got a machine with expensive gettimeofday() and you have > to take your measurements with an appropriate quantum of salt. > > regards, tom lane
Interesting.. Direct query: Time: 374336.514 ms Indirect query: Time: 387114.059 ms Mystery solved. Thanks again Tom. For what it’s worth: Linux 3.2.0-4-amd64 Debian 3.2.46-1+deb7u1 x86_64 >
