I haven't had time to look into this yet in great detail, but I noticed that HSQLDB now supports sequences, supposedly as of 1.7.2.
http://www.hsqldb.org/doc/guide/ch02.html#N104E1 I'll probably take a look at implementing this sometime soon (after I deal with my existing Cayenne issues). Auto-increment identity columns are also supported. I'm not interested in identity columns (as primary keys) so this is just a FYI. http://www.hsqldb.org/doc/guide/ch02.html#N104B3
