If you want something standalone, try DBD::RAM. You can still have the SQL syntax and whatnot without the server. However, you then do not get the benefits of a server, such as threading, indexing, locking (heaven forbid someone changes your flat files), control over who accesses your data, etc... Out of curiosity, why do you want it standalone? Because you don't want to muck with a server, or a design reason of some sort?