Oracle Isolation Level and ADO

Hi,

I have some COMs developed in Visual Basic. These COMs access to an
Oracle DB with ADO. it isn't set the Isolation level of the transaction
on the ADO Connection and i think that ADO use the default Level "Read
Committed".

This is the pseudo-code:

***********************************
BEGIN TRANSACTION

<<LOCK table1 exclusive mode>>

idNew=SELECT MAX(TABLE1.id)+1 FROM TABLE1
Insert into TABLE1 (ID) values (idNew)
.....
COMMIT
or
ROLLBACK

***********************************

Then the explicit LOCK grants that two invocations of this code don't
read MAX value two times.

Is the explicit LOCK useless in this code?

I know that all the Isolation Levels do strict 2PL on write locks. The
isolation level impact only on read locks.

What is the right Isolation Level?

I think that "Serializable" should be equvalent to the explicit LOCK on
the tables.

Bye

Ken

.

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