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Transaction Isolation Level

seema mani
Ranch Hand

Joined: Sep 30, 2001
Posts: 49
hi
I'm confused about the Transaction Isolation level of ejbs.
for eg: The isolation level setting of 'Repeatable Read' is defined in the EJB book by OReilly as follows - The transaction cannot change data that is being read by a different transaction.
My doubt is like this - Suppose there are 2 transactions- t1 and t2. t1 has the isolation level set to 'Repeatable Read' and
t2 has the isolation level set to 'Read Uncommitted'.
Now if t1 reads some data which of the following is true ?
a. t1 cannot change data read by t2
b. t2 cannot change data read by t1
c. both a and b
Please advise even if you feel its a stupid question.
Its just not clicking.
Thanks a lot
seema


Sun Certified Java Programmer<br />Sun Certified Web Component Developer<br />Sun Certified Business Component Developer
nan sh
Ranch Hand

Joined: Jan 05, 2001
Posts: 167
In your situation, ti and t2 can not be different islation level.


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It is sorta covered in the JavaRanch Style Guide.
 
subject: Transaction Isolation Level
 
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