Сoordinates only users geolocation in RoR 3
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I'm looking for a solution to build very simple geolocation-based app. It should keep current user location, and select users near specific coordinates. So I don't need a solution, based on foursquare or google map apis, I need something more simple. 

Now I have model user, which have :lat and :long fields, and query like this:

    "SELECT lat, long FROM users WHERE long < :lolow AND long > :lohigh AND lat < :lalow AND long > :lahigh"

Is there any more elegant way to do this? Thank for advise!