Jeremy Palmer <JPalmer@xxxxxxxxxxxx> writes: > This is the query that does not use the indexes: > SELECT > coo.nod_id, > 6400000*radians(sqrt((coo.value1 - -41.0618)^2+((coo.value2 - 175.58461)*cos(radians(-41.0618)))^2)) as distance > FROM > crs_coordinate coo > WHERE > coo.value1 between -41.0618-degrees(1200.0/6400000.0) and -41.0618+degrees(1200.0/6400000.0) and > coo.value2 between 175.58461-degrees(1200.0/6400000.0)/(cos(radians(-41.0618))) and 175.58461+degrees(1200.0/6400000.0)/(cos(radians(-41.0618))); Those expressions yield float8, not numeric, and numeric vs float8 isn't an indexable operator for reasons we needn't get into here. You should probably rethink whether numeric is really the best choice of datatype for your columns, if this is the sort of value you expect to work with --- you're paying a considerable price in speed and space for perhaps-illusory precision gains. But if you insist on using numeric then the solution is to cast the expression results to numeric explicitly. BTW I wonder whether you ought not be looking into postgis rather than rolling-your-own coordinate arithmetic ... regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
