zerebubuth/openstreetmap-cgimap — pull request #25 by pnorman (2013-07-11 09:44:32+00:00)
Title: Short-circuit empty areas on the map? call

If there are 0 nodes in the bbox then all the subsequent SQL will have
no effect, so we can just skip it.

My test log is probably empty area heavy compared to the api.osm.org traffic, but I got a 6.1% speed increase, which is pretty substantial.