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A confused mock question

 
Denis Wang
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What is the answer? Is the answer based on legacy EJB implementation?
As far as I understand of EJB 2.0, BMP has no definite advantage over CMP as far as performance is concerned.
When should you use CMP?
(A) When performance is essential and you are storing standard data types.
(B) When performance is not essential and you are storing standard data types.
(C) When performance is essential and you are storing complex data types.
(D) When performance is not essential and you are storing complex data types.
 
Ian B Anderson
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Hello Dennis,
But this version of the SCEA is based upon EJB 1.1 not EJB 2.0. Therefore the question should be answered with this in mind.
For example, in Cades SCEA guidebook on page 24: "CMP does not generate the most efficient SQL queries", and at the end of the chapter: "... The downside to CMP is that the tools are not mature enough to provide the performance necessary for an enterprise application." This however is no longer the case as modern EJB Containers can apply many optimization techniques and out perform BMP.
Regards
Ian
 
Denis Wang
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thanks.
 
Rufus BugleWeed
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AFAIK, the J2EE community has learned that the performance of CMP is often equal or better than BMP.
 
Luciano Queiroz
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The answer to this question is:
(B) When performance is not essential and you are storing standard data types.
 
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