> You can also use "cdataport" Ant task available in Cayenne 1.2. It  can 
> help you with plain tables and data. It does not implement  porting of 
> indexes, stored procedures, triggers and views, but if you  are on 
> MySQL, you are probably free from that "baggage" anyways ;-)
> 
> The sequence of steps is roughly the following:
> 
> * Get Cayenne 1.2M7 (http://objectstyle.org/cayenne/) - it supports  
> both MySQL and Derby.
> * Fire up CayenneModeler, point it to MySQL and reverse engineer the  
> schema. Save the mapping file somewhere.
> * Create an Ant build file with "cdataport" task pointing to your  
> mapping file and both databases (see chapter 13.4 of the user guide  
> bundled with Cayenne for the Ant task details).
> * Run it with Ant to transfer the data.
This just sounds fantastic.
IMHO such a cool feature should be directly in the Cayenne Modeler in the menu:
"Migrate Data" :).

Than by calling that menu item, to trigger those steps automatically :).
After that, one can put in the Derby FAQ: "How to migrate to Derby from other DBs with just a few 
clicks" :).

Thanks in advance,

Ahmed.