Avoiding deadlocks Using both row-level locking and the TRANSACTION_READ_COMMITTED isolation level makes it likely that you will avoid deadlocks (both settings are defaults). However, deadlocks are still possible.

application developers can avoid deadlocks by using consistent application logic; for example, transactions that access Accounts and Orders should always access the tables in the same order. That way, in the scenario described above, Transaction B simply waits for transaction A to release the lock on Orders before it begins. When transaction A releases the lock on Orders, Transaction B can proceed freely.

Another tool available to you is the LOCK TABLE statement. A transaction can attempt to lock a table in exclusive mode when it starts to prevent other transactions from getting shared locks on a table. For more information, see "LOCK TABLE statement" in the .