Has anyone ever tried to persist Drools Flow processes to HBase (or some other NoSQL DB)? We are working on a cloud-based system sitting with HDFS and HBase for storage. We would rather not introduce a RDBMS into the architecture simply to support Drools Flow's JPA requirement for persistence. I've looked at datanucleus' JPA implementation which can talk to HBase, but from my limited knowledge of JPA, it doesn't look like their JPA for HBase implementation supports the Drools JPA requirements. Specifically, HBase does not support generation of record IDs, joins, or inner selects. Similarly, it doesn't look like the Hadoop JDBC driver (with Hibernate) will work for the same reasons. Regards, Dan Nathanson