Walter, thank you very much for trying to explain that to me. Unfortunately I've got lost somewhere in the middle of your response... >>- If you are updating or deleting just one row, then no conflict can happen >>with your settings. But if you want >>to update or delete several rows then >>conflicts can happens.
In my test case I have two threads (or applications, I do not think that does have matter) which are constantly updating the same row. >>- Transaction T1 starts, transaction T2 starts, transaction T1 wants to >>update some rows, transaction T2 >>wants to update some different rows. No >>problems until now. This is not my case because my transactions are working on the same row but so far I understand that, and I agree with you. Different rows, no deadlock should happen. >>Transaction T2 wants to update (and therefore blocks) a row and after that >>transaction T1 wants to update >>that row. Deadlock because transaction T1 is >>older than transaction T2. I do not understand, why deadlock? Why T1 does not wait for T2 to commit/rollback? >>If transaction T1 blocks a row and after that transaction T2 wants to update >>that row then transaction T2 will >>wait. But if transaction T2 blocks a row >>and after that transaction T1 wants to update that row will have a >>>>deadlock. I do not understand this, why there will be a deadlock? Because the older transaction could not be first to block the row? I thought I've had all figured out:(
