Social networking and voting site Digg is rewriting its underlying software infrastructure in an effort to improve performance and scalability. Part of that effort involves moving away from the MySQL database that has helped to power Digg since its creation. In MySQL's place, Digg is going with an open source NoSQL non-relational database called Cassandra that was originally created by Facebook. As part of the migration effort from MySQL to Cassandra, Digg developers built a tool to help move data from one database to the other. The tool could soon be open source, helping other developers make the same move.