On Wed, 2003-01-08 at 22:45, Matthew Baird wrote: > I disagree with your statement of
> "Let's face it, O/R mappings will never be very efficient. " > > Both OJB (to which I contribute) and Hibernate (which I watch closely) > approximate raw JDBC performance in most cases, and can exceed it in many others. > Go check out the performance target in OJB, and Hibernate documentation > goes over performance extensively. Both are GREAT projects, but neither is CMP. Yes, but here you are making the assumption that JDBC is efficient, which it isn't. JDBC is an abstraction layer itself, as it the SQL (which must generally be parsed and compiled) that it executes. If you think about the big picture, you will notice how much extra work is being done just to make the relational model fit the object model. O/R mapping layers: Your code -> O/R mapping layer -> JDBC -> SQL -> datastore. That's quite a lot of repackaging before you finally access the information in the database. The above will *never* be as efficient as this: Your code -> datastore. But even this could be an improvement: Your code -> CMP layer -> datastore. Additionally, relational databases are usually separate processes, so JDBC also loses out because of the IPC/RPC and the marshalling and unmarshalling of data. Performance would be dramatically improved if the datastore was in the same process and had a minimal amount of marshalling to do. -- Peter Beck BEng (hons) - Managing Director, Electrostrata Ltd. http://www.electrostrata.com --+-+-- Experts in e-business and e-commerce ------------------------------------------------------- This SF.NET email is sponsored by: SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See! http://www.vasoftware.com _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
