On Thu, Dec 23, 2010 at 09:33, Jie Li <jay23jack(at)gmail(dot)com> wrote:
> While the first sorting takes
> about only 6 seconds, the second one takes over 30 seconds, Is this too
> much than expected? Is there any possible optimization ?
If you're doing these queries often, you should:
CREATE INDEX ix_big_wf_age_id ON big_wf (age, id)
If that's still not fast enough, you can physically sort rows in the
table using the newly created index:
CLUSTER big_wf USING ix_big_wf_age_id;
Please post back your results. :)
Regards,
Marti