Praveen Kumar N wrote:
>
> Following is the output of query i have executed.
Looks like Alvaro guessed right. It reads both relations in sequence,
sorts them in temporary storage, outside bufmgr, and then does a merge
join on the sorted inputs.
If you want to see the behavior you expected, I think you need to define
indexes on a2 and b2, if you don't have them already, and coerce the
planner to choose a nested loop join. I'd suggest using "SET
enable_seqscan=false; SET enable_bitmapscan=false;" and see if that gets
you a nested loop join.
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com