They're completely different, unrelated products. Their similarities are that they're relational database that implement SQL, and that JDBC drivers are available for both. Their full feature lists can be found on their respective web sites.
posted 6 years ago
They are two different DBs.
java DB must be based on java,it is Sun's database.
mysql can be used for many languages, such as C、C++、Eiffel、Java、Perl、PHP、Python、Ruby and Tcl