Re: Using indexes for ORDER BY and PARTITION BY clause in windowing functions

Sameer Kumar <sameer.kumar@ashnik.com> writes:
> I am not sure why but my PostgreSQL does not seem to be using indexes for
> ORDER BY clause or PARTITION BY CLAUSE which I use with windowing function.

When the entire contents of the table have to be read, a seqscan-and-sort
will frequently be estimated as cheaper than an indexscan.  If you think
this is not true on your hardware, you might need to adjust
random_page_cost.
        regards, tom lane