In computing, a DBM is a library and file format providing fast, single-keyed access to data.
A key-value database from the original Unix, dbm is an early example of a NoSQL system.
The two resulting child buckets will themselves split when they become full, so the database grows as keys are added.
The dbm library and its derivatives are pre-relational databases – they manage associative arrays, implemented as on-disk hash tables.
[2][10] After a change of licensing of the Berkeley DB to GNU AGPL in 2013, projects like Debian have moved to LMDB.