Re: How to begin a transaction PART II

ISOLATION_LEVEL = { SERIALIZABLE | READ COMMITTED } The ISOLATION_LEVEL parameter specifies how transactions containing database modifications are handled. ISOLATION_LEVEL is a session parameter only, not an initialization parameter.

• SERIALIZABLE indicates that transactions in the session use the serializable transaction isolation mode as specified in SQL92. That is, if a serializable transaction attempts to execute a DML statement that updates rows currently being updated by another uncommitted transaction at the start of the serializable transaction, then the DML statement fails. A serializable transaction can see its own updates.

Given that the transaction is already set to serializable isn't it clear that it MUST be read-write?

Carlos Hernández wrote:

> Ok. I undertand the concepts.
>
> But, if I would like change the isolation level of a transaction (via SQL
> Plus) and initiate the transaction on the next line on mode Read Write?
>
> This code on PL/SQL via SQL PLUS not runs:
>
> set transaction isolation level serializable;
> set transaction read write; ( <- ORA-01453 )
>
> Update ....... (Begin the transaction)
>
> Commit;
>
> How to change the isolation level and mode read/write on the same
> transaction?
>
> Thanks.
>
> Carlos Hernández
> Barcelona (Spain)
>
>
>
>
Received on Fri Feb 08 2002 - 10:52:19 CST