MDBC is a JDBC driver that provides an application programmer a way to automatically copy data to and from a running copy of MUSIC/Cassandra. The driver does this by intercepting all DELETES, INSERTS, SELECTS, and UPDATES and copying modified table rows to and from Cassandra.

MDBC can automatically adopt to the database in use, as well as the style of MUSIC interaction, by the use of "mixins". Each JDBC Connection via MDBC specifies two mixins to use:

• a Mixin that conforms to the {@link org.onap.music.mdbc.mixins.MusicInterface} specification for communicating with MUSIC/Cassandra.
• a Mixin that conforms to the {@link org.onap.music.mdbc.mixins.DBInterface} specification for communicating with the underlying database in use.

More details are provided on the package pages for org.onap.music.mdbc and org.onap.music.mdbc.mixins.

Limitations

• The java.sql.Statement.executeBatch() method is not supported by MDBC. It is not prohibited either; your results will be unpredictable.
• When used with a DB server, there is some delay as dirty row information is copied from a table in the database, to the dirty table in Cassandra. This opens a window during which all sorts of mischief may occur.