SQLite is a small fast embedded SQL database engine.
DBD::SQLite embeds that database engine into a DBD driver, so
if you want a relational database for your project, but don't
want to install a large RDBMS system like MySQL or PostgreSQL,
then DBD::SQLite may be just what you need.
It supports quite a lot of features, such as transactions (atomic
commit and rollback), indexes, DBA-free operation, a large subset
of SQL92 supported, and more.