What happened when you remove "and st_value (dted_elevations.rast, f.geom) is not null"? You get null values?
Do you have many nodata values in your raster? How is your raster tiled? Did you build a spatial index on the raster tiles? Pierre > -----Original Message----- > From: [email protected] [mailto:postgis-users- > [email protected]] On Behalf Of Gold, Jack L (US SSA) > Sent: Friday, May 09, 2014 1:01 PM > To: '[email protected]' > Subject: [postgis-users] Dted elevations > > I know this question has already been answered a hundred times but I am > at a remote location currently with only email access right now and I hope > someone can help. The following query is taking close to a second to run > and I think it should be much faster. > > Select st_value from (with f as ( select st_transform ( st_SetSRID( > st_MakePoint('106','32'), 4326) as geom) select > st_value(dted_elevations.rast, f.geom) from dted_elevations cross join f > where st_intersects ( dted_elevations.rast , f.from) and st_value > (dted_elevations.rast, f.geom) is not null) as st_value; > > Any help is greatly appreciated. > > Jack Gold > _______________________________________________ > postgis-users mailing list > [email protected] > http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users _______________________________________________ postgis-users mailing list [email protected] http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users
