Handling Deadlocks

When an instance of the Microsoft SQL Server Database Engine chooses a transaction as a deadlock victim, it terminates the current batch, rolls back the transaction, and returns error message 1205 to the application.

Your transaction (process ID #52) was deadlocked on {lock | communication buffer | thread} resources with another process and has been chosen as the deadlock victim. Rerun your transaction.

Because any application submitting Transact-SQL queries can be chosen as the deadlock victim, applications should have an error handler that can trap error message 1205. If an application does not trap the error, the application can proceed unaware that its transaction has been rolled back and errors can occur.

Implementing an error handler that traps error message 1205 allows an application to handle the deadlock situation and take remedial action (for example, automatically resubmitting the query that was involved in the deadlock). By resubmitting the query automatically, the user does not need to know that a deadlock occurred.

The application should pause briefly before resubmitting its query. This gives the other transaction involved in the deadlock a chance to complete and release its locks that formed part of the deadlock cycle. This minimizes the likelihood of the deadlock reoccurring when the resubmitted query requests its locks.

See Also

Concepts

Deadlocking
Detecting and Ending Deadlocks
Minimizing Deadlocks
Handling Errors and Messages in Applications

Help and Information

Getting SQL Server 2005 Assistance