One thing missed here is this sort of thing is a lot easier (to read and code) using the built-in earthdistance module. The query doesn't need the added "shape

One thing missed here is this sort of thing is a lot easier (to read and code) using the built-in earthdistance module. The query doesn't need the added "shape" column unless you want it for indexes, and becomes simply: SELECT d.city, d.state, earth_distance( ll_to_earth(d.latitude, d.longitude), ll_to_earth(l.latitude, l.longitude)) as distance FROM dennys d, laquinta l WHERE distance <= 150 ORDER BY 3 No more magic numbers or confusing function names. Note I don't mean this as a slight on the article - I purely mean it to educate postgres users that they can do this sort of thing easily without downloading/installing PostGIS.