If you want to use a SQL database without requiring administrative hassles, that means SQLite. SQLite is the DB of choice for most smart phone applications. I use the SQLite Manager plug-in for Firefox to view existing databases on my Windows PC.

SQLite is a simple: one file <=> one database. There are no passwords or users. If my process can access the DB file, then I can use the Perl DBI to connect to it, read it and modify it.