> -----Mensaje original-----
> De: Scott Marlowe [mailto:scott(dot)marlowe(at)gmail(dot)com]
>
>
> Note that if you are storing your time stamp as timestamptz,
> you can use the "at time zone 'xyz'" construct to create an
> index, and as long as you retrieve them with the same
> construct you'll get to use the index.
>
> create index test_ts_month_trunc on testtable
> (date_trunc('month',(ts at time zone 'MST')));
> select * from testtable
> where date_trunc('month',(ts at time zone 'MST'))='2007-10-01
00:00:00'::timestamp;
>
I see the point. Thanks for the elaboration.