Embeddable SQL Database Enginehttp://www.sqlite.org/
SQLite is a C library that implements an embeddable SQL database
engine. Programs that link with the SQLite library can have SQL
database access without running a separate RDBMS process.
SQLite is not a client library used to connect to a big database
server. SQLite is a server and the SQLite library reads and writes
directly to and from the database files on disk.
SQLite can be used via the sqlite command line tool or via any
application that supports the Qt database plug-ins.