When you upgrade MySQL from 4 to 5 there’s a decent chance you’re going to be seeing some Error #1054 action on any query with a left join.

There’s a description and solution available at CodingForums.com.

Just recently I wrote a small program for some friends that tracks visitors to their MySpace pages (maybe I’ll write more about that in the future). To get the geographical location of each visitor I used a service by MaxMind called GeoIP.

Instead of buying one of their site licenses I went with their web services package. For $20, I can run 50,000 IP queries against their database and get the IP’s city, state, country and more returned to me. Code examples to make this work are available on the MaxMind site.

If you’re in the market for a low cost way to do geolocation on a small amount of data you should give MaxMind’s GeoIP web service a look.