ORA-08177: can't serialize access for this transaction

[haltun]

Delphi 5
DOA 345
Oracle 8.0.5

I got the error "ORA-08177: can't serialize access for this transaction" when I run a SQL using TOracleQuery (Insert SQL).

Session.ThreadSafe := True;
qry.Session.SetTransaction(tmSerializable)

What causes this error?

Thank you..

 

[Marco Kalter]

Cause: Oracle encountered data changed by an operation that occurred after the start of this serializable transaction.

Do you really need serializable transactions?

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Marco Kalter
Allround Automations

 

[haltun]

I don't do any update or Delete operation. I'am using TOracleQuery and my SQLs are only insert statements.

My application is multithreaded and I just do insert operations in the transaction. In this case I am not sure if I really need Serializable Transaction.

In MultiThreaded Applcations, is there any special need for using Serializable Transactions or can I use ReadCommitted safely in my case (just insert operation in one table)

Originally posted by mkalter:
Cause: Oracle encountered data changed by an operation that occurred after the start of this serializable transaction.

Do you really need serializable transactions?

 

[Marco Kalter]

The default "read committed" isolation level should be appropriate for most applications. Serializeable isolation level ensures that you see a consistent database state for the duration of your transaction, but it has some database requirements (no large update transactions, sufficient rollback segment space), and you risk additional ORA-08177 exceptions.

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Marco Kalter
Allround Automations