----- Original Message -----
Sent: Thursday, October 03, 2002 1:57
PM
Subject: Concurrent record update
Hi,
I have some
questions about blocking concurrent update with multiple
clients.
I have
the following schema of transaction :
User A
User B
1. SELECT * FROM
TEST
2.
SELECT * FROM TEST
3.
UPDATE TEST SET .... WHERE TEST_ID = n
4. UPDATE TEST SET
..... WHERE TEST_ID = n
In this schema,
two users are updating the same record but update from
B is lost ....
How can i do that
in my SessionBean, to throw an exception for user A when he tries
to
update the record
?
I have read some
articles about database isolation level and transaction level in EJB
world
but i don't see
how to apply them to my case.
Thanks for your
help
Sebastien
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