This driver uses a database table to store the cache. The newest versions of MySQL and SQLite work are known to work. Other RDBMSes should work. Why cache things in a database? Isn't the database what people are trying to avoid with caches? This is often true, but a simple primary key lookup is extremely fast in many databases and this provides a shared cache that can be used when less reliable storage like memcached is not appropriate. Also, the speed of simple lookups on MySQL when accessed over a local socket is very hard to beat. DBI is fast. WWW: https://metacpan.org/release/CHI-Driver-DBI