I'm using JBOSS 2.4.3 and oracle 8. My Isolation level in Jboss.jcml is TRANSACTION_SERIALIZABLE. I have two clients accessing the same db record. The second update overwrites the first. My understanding is that concurrent access with SERIALIZABLE is not possible. Also if I change the isolation level to REPEATABLE_READ, the container says that only READ_COMMITTED and SERIALIZABLE is allowed. Any help will be appreciated.
Oracle 8 only supports READ_COMMITTED and SERIALIZABLE.
If you select SERIALIZABLE and Oracle detects a serialization problems, you should have ORA-08177 SQLExceptions.