[postgis-users] Query help

[Stephen Crawford]

Hello All,

I have a query that gets the name and id of all the features from table Y
that intersect a feature fro table X:

SELECT DISTINCT(m.mlra_name) AS name,m.mlra_reg_s as id FROM mlra AS m,
mo_org AS o
WHERE m.the_geom && o.the_geom
AND intersects(m.the_geom,o.the_geom)
AND o.mo = 1;

Is this an efficient way to write this query? I have a gist index on the
mlra table, so I included the line:

WHERE m.the_geom && o.the_geom

In hope that it would speed things up, because it should use the gist index.
Am I correct?  It doesn't seem to make a difference.  I run  vacuum analyze.
How can I check the geometry stats, and how can I tell if the index is being
used?

Thanks,
Steve


Stephen Crawford
Center for Environmental Informatics
GeoVISTA Center
The Pennsylvania State University
814.865.9905
src176 at psu.edu