title: sql query for points in polygon/rectangle
body: <p>Ok, so I have a very large database of property information, complete with geographic coordinates. What I need to be able to do is run a query that asks, "give me all properties that are inside a given rectangle or polygon." The user interface would allow the user to define the points of the rectangle or polygon (using a map system). These coordinates would go into the query and sql should return a list of properties in that area. If polygon isn't possible, at least a rectangle would be helpful. I already know how to do the radius search.</p>
  
  <p>Appreciate any help you can provide.</p>