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Could you please describe some specific scenarios where BMP should be used?
BMP is seldom use and according to HF EJB, there are rare cases that you can make use of BMP. Might be you must have specific transactions that are break into several level, and each level must commit certain data, and when exception occurs in 1 transaction do NOT require to rollback other transactions, while this happened for a particular transction, you then have to implement your own transaction management logic.
For join queries can we use CMP 2.0 ? Does Containers supports mapping in this case?
Yes, CMR - Container Managed Relationship is aimed to provide this support, to link up various tables using Entity Beans.
Originally posted by Mathew Sam: Could you please describe some specific scenarios where BMP should be used? For join queries can we use CMP 2.0 ? Does Containers supports mapping in this case?
Mathew: As Nick said, for sake of robustness and to reduce the development time, it's always a good idea to use CMP, and CMP works pretty well in EJB 2.0. However, BMP does offer you more flexibility. There may be situations where you may need to use BMP (that's why BMP option is there), for example consider the situation when the data storage you are using is not supported by CMP (e.g. you are dealing with the data that exists in an application rather than the database). So, the bottom line is, use CMP whenever you can. Cheers. Paul Book website http://www.manning.com/sanghera
Paul Sanghera, Ph.D.<br />SCBCD, SCJP, Project+, Network+, Linux+, CNA.