I am trying to run the following query to determine the area and number of points of a polygon:
Select osm_id, st_npoints(the_geom) as numPoints, st_area(transform(the_geom, 3395))/1000000 as areakm2 from water_table where st_isvalid(the_geom);
I receive the following error:
Input geometry has unknown (-1) SRID
Anyone know what the problem is?