Cloudscape was always a lightweight embedded database, but when IBM contributed Apache Derby they also contributed a TCP/IP network server that speaks Distributed Relational Database Architecture (DRDA) protocol -- the lingua franca of relational databases.
Any database driver that speaks DRDA can talk to Derby over TCP/IP; the most common examples include:
- JDBC: both the IBM DB2 Universal JDBC driver and the open source Derby driver contributed by IBM
- CLI / ODBC: the IBM DB2 Universal Database client provides a C interface for translating CLI/ODBC calls into DRDA
As there is currently no open-source DRDA implementation for a CLI/ODBC driver, this tutorial relies on the use of the DB2 client to provide access to Derby from Perl, PHP, and Python.