Have a look at Axion for a pure java db
http://axion.tigris.org/
Not as full featured,but still useful.
Er, I take it that "not as full featured" is an example of meiosis :-)
Here's what the web page says:
----------------------------------------
Not (Yet) Supported Features
*
ALTER TABLE (other than add/drop constraint)
*
client/server mode
*
constraints/foreign keys (partial support is available)
*
GROUP BY/HAVING
*
stored procedures
*
sub-selects
*
triggers (note that default column values are supported)
*
user-level security
----------------------
This is basically a small embedded db engine, not an enterprise class RDBMS.
cheers
andrew
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