[hibernate-dev] hibernate/jpa for non-relational databases

Hi, I would like to get your opinion on providing Hibernate-backed JPA implementation for non-relational storage. Given rising popularity and variety of key-value stores and the fact that often they provide subset of functionality found in relational databases, it might make sense (especially for web-scale companies that most likely will be using number of storage technologies) to leverage Hibernate model for key-value stores. Perhaps only a subset of features and subset of the querying capabilities. As relations between entities in key-value stores are done on client side, the possible implementation could include some form of relational engine (similar to what Carbonado[1] and Oracle's DPL[2] do for BerkeleyDB) to provide (partial) support for query language. Providing caching, entity lifecycle management, validation and even transactions should be rather easy as those are orthogonal concerns. WDYT? Do you see Hibernate/JPA catering for scenarios that leverage key-value stores? Do you see any major impediments either in Hibernate implementation or JPA philosophy that would make such extension not worth the effort? Cheers, Tomasz ps: sample project along similar lines of thinking: http://code.google.com/p/simplejpa/ [1] http://carbonado.sourceforge.net/ [2] http://www.oracle.com/database/berkeley-db/je/index.html