ObjectDB and DB4O are the only two real object database I known. Why didn't you give a comparison between them in JPA Performance Benchmark (JPAB)?
TIA
ObjectDB vs DB4O comparison
#1
gzdillon
#2
support
The focus of JPAB is JPA implementations and ObjectDB is the only object database that supports JPA.
However, since DataNucleus provides partial JPA support for DB4O - it makes sense to extend the benchmark to include this combination as well.
Thank you for this idea.
Update (2012-02-29): DB4O (with DataNucleus) is now included in the JPAB benchmark.
ObjectDB Support