Unless you use the explicit join syntax:
select p.* from A p join B q on (p.id = q.id)
and also set join_collapse_limit= 1
The order of the joins is determined by the planner.
Also explain is your friend :)
________________________________
From: Adarsh Sharma <adarsh.sharma@orkash.com>
To: pgsql-performance@postgresql.org
Sent: Monday, August 1, 2011 11:42 PM
Subject: [PERFORM] Which Join is better
Dear all,
Just want to know which join is better for querying data faster.
I have 2 tables A ( 70 GB ) & B ( 7 MB )
A has 10 columns & B has 3 columns.Indexes exist on both tables's ids.
select p.* from table A p, B q where p.id=q.id
or
select p.* from table B q , A p where q.id=p.id
Thanks
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