Today I migrated successfully this Blog from a Derby DB into a MySQL Database.
From the Apache Blog Software Roller this is no big deal. And as I run the blog on a Glassfish Server there was only a new JDBC Database Pool necessary which is connected to the JDBC Ressource used by the roller web app (jdbc/rollerdb).
But what to do with all the data? Therefore I used the open source software tool OpenDBCopy. With this tool you can migrate the data from one database system into another database system independent form the platform.
As there was no provided Derby Driver Setting provided I used "PostgreSQL" as a dummy and edited the driver class and url setting as you can see in the first picture.
To migrate the data from one database into another it is necessary that in both databases the database scheme still exists. Also as the destination database is still empty. To get the database schema created on my mySQL database I started roller first with the new mysql database connection to force roller to create a new database schema. So next I was able to copy my data from the source database (Derby) to the destination (MySQL) successfully with openDBCopy:
That's it. Next I restarted my web server and now my blog runs on MySQL with all the data.
Thanks to the developers from OpenDBCopy!