Yet another dumb question

[Sajid Moinuddin]

Hi all,
I know it sounds very stupid, but what is the difference between
"REQUIRES NEW" And a Nested transaction?? To me both seems same. Someone please explain.
regards,
Sajid

[Balaji VR]

Good catch :-)

Both of them might look alike, but they are quite different.

For example, Nested transactions can operate concurrently, where as the "REQUIRES NEW" stuff will make the callee to wait until the spawned transaction returns back!

EJB Spec (page no. 332) makes clear why nested transactions are not supported.

Note: The decision not to support nested transactions allows vendors of existing transaction
processing and database management systems to incorporate support for Enterprise Java-
Beans. If these vendors provide support for nested transactions in the future, Enterprise Java-
Beans may be enhanced to take advantage of nested transactions.

[satheesh krishnaswamy]

Thanks Balaji for the explanation.I too had that doubt.It got cleared now.
B.T.W when did u passed SCBCD? I didn't see that post at all

[Balaji VR]

I did that by 27th of April

[satheesh krishnaswamy]

Oh! congrats.Nice Score

Can you share your Exam experience with us,Please.

[Balaji VR]

Well, I took about 40 days for the full preparation. I started with Mastering EJB book. Then I printed out EJB spec and bought HFEJB book. I read them parallely. Once I am done with HFEJB, I was reading only EJB spec

Once I became confident of the EJB conepts, I took the mock exam in HFEJB book. The next day I took EJBCertificate.com mock exam. 2 days after that, I gave SCBCD exam.

Thats it!!!