ninejaguar asks: "Slashdot did an article on an Open Source product called Prevayler, which could theoretically resolve all the problems associated with OO's rough courtship with Relational databases. Slashdot covered Prevayler when it was still 1.x. Despite fear, doubt, and memory concerns, it has reached 2.0 alpha. Is anyone currently using this non-database solution in production? If so, has it sped development because of the lack of OO-to-RDBMS complexity? Was there a significant learning curve to speak of? The LGPL'd product could be incorporated into proprietary commercial software, and few might know about it. Is anyone considering using it in a transactional environment where speed is the paramount need? And, are there any objections to using Prevayler that haven't been answered at the Prevayler wiki? Would those who use MySQL find Prevayler to be a better solution because it's tiny (less than 100kb), 3000 times faster and is inherently ACID compliant?" Update: 09/24 19:25 GMT by C :Quite a few broken links, now fixed.
"We've used relational databases for years despite incompatibilities in SQL implementation. Accessing them from an OOP paradigm has been so tedious, that Object-Relational mapping technologies have sprouted all over the Open Source landscape. Some competing examples and models are Hibernate, OJB, TJDO, XORM, and Castor; which in turn have supporting frameworks such as Spring and SQLExecutor. Because SQL is the dominant form of interfacing with the data in an RDBMS, there's now a specification to offer it a friendlier OO face.
Most of the above, including the SQL-variants, arguably appear to add yet another layer of complexity (even if only at the integration level) where they should be taking complexity away. These solutions are put together by some very smart people, but it's inescapable to get that feeling someone is missing the forest (simple answer) because all the trees (incompatible models) are in the way. If there are so many after-the-fact solutions attempting to simplify relational database access and manipulation from OO, isn't it reasonable to think that there is something generally wrong with trying to cobble-together two disparate concepts with what are essentially high-caliber hacks? Is Prevayler a better way?"