Re: query not using index

=?ISO-8859-1?Q?Greg_Jan=E9e?= <gjanee@alexandria.ucsb.edu> writes:
> db=> explain analyze SELECT * FROM scene A WHERE A.footprint && box
> '((-120.1, 34.3), (-119.7, 34.4))' ;
>                                                      QUERY PLAN
> ------------------------------------------------------------------------
> -------------------------------------------
> Seq Scan on scene a  (cost=0.00..369700.89 rows=42196 width=252)
> (actual time=50.064..47748.609 rows=507 loops=1)
>     Filter: ((footprint)::box && '(-119.7,34.4),(-120.1,34.3)'::box)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> Total runtime: 47749.094 ms
> (3 rows)

This appears to be using the "box && box" operator.  I'm not sure which
operators a GIST geometry index supports, but evidently that's not one
of them.  You probably want to cast the other operand differently.
How, I dunno --- the postgis lists would be a better place to ask
than here.

            regards, tom lane