Interbase

Interbase was created by Groton Database Systems in 1984 and funded by Apollo Computer. In 1986 Apollo decided to exit the software business and gradually sold Interbase to Ashton-Tate between 1986 and 1991. Borland acquired Ashton-Tate in 1991 and obtained Interbase as part of the deal. Borland wanted to form a new company dedicated to Interbase and release the database as open-source, however agreement on separation terms of the companies was not reached. Interbase 6 became an open-source product (out of which Firebird was forked) and Borland continued work on proprietary Interbase code.

Interbase today is a mature product, but never quite reached the top. Its strength is MVCC (multi-version concurrency control), which keeps separate copies of data for each transaction, thus avoiding locking while in use. However, that makes the database grow very quickly, so the database must be swept periodically. During that operation, every row in every table in the database is visited and obsolete copies of its data are deleted.

It’s very easy to maintain Interbase - and it has a very small footprint. Its full installation (server and client) is less than some other databases’ client-only part.

Interbase server will refuse to work with old database files, so if you are upgrading the database server, you will need to back up your database on the old server and then restore it after upgrading the server.