If the Stored Procedure is run at the same time for the same key in two concurrent sessions the deadlock can occur. A. deadlock-list deadlock victimprocess3e9ada8 process-list process idprocessbaf048 taskpriority0 logused20022 waittime3890 schedulerid1 kpid1304 statussuspended spid59 sbid0 ecid1 priority0 transcount0 lastbatchstartedT15:46:53.263 lastbatchcompletedT15:46:53.263 clientapp.Net SqlClient Data Provider hostname. It’s the “IF EXISTS” which reads the row and holds a RangeS-S lock for the duration of the transaction. 1- reduce the LOCKTIMEOUT in db that applications do not wait a long time 2- Index all fields in blocking tables to shorten query times If anybody can suggest an avenue of search or an alternative to prevent or minimize this error. Other transactions cannot insert new rows with key values that would fall in the range of keys read by any statements in the current transaction until the current transaction completes. In a simple situation, the most general advice applies, and that is to touch the tables in the same order each time when constructing queries. From this graph, you can deduce what caused the deadlock. That way people like me will continue to have jobs, cleaning up behind people such as yourself. You can also click the deadlock tab in the Details section to view the deadlock graph. If you believe that constantly updating your stats is a way to prevent deadlocks in SQL Server, then you should find a new line of work. No other transactions can modify data that has been read by the current transaction until the current transaction completes. Since SQL Server looks for deadlocks every 5 seconds and kills the query that’s the easiest to roll back, we were able to see the deadlock victim emerge. Double-click on the process to open the XML report. This keeps the cursor from locking the actual data table and the only locks you get are for the updates or inserts performed inside the cursor which are only held for the duration. The documentation mentions the following behavior for this level of isolation: While cursors are slow in SQL Server, you can avoid deadlocking in a cursor by pulling the source data for the cursor into a Temp table and running the cursor on it. The existence check is performed with the “IF EXISTS(SELECT…)”. VALUES stored procedure is doing an UPDATE or an INSERT based on the existence of the row inside the table. SET ProductID = TransactionDate Quantity = ActualCost = TransactionID = INTO ( IF EXISTS(SELECT 1 FROM WHERE TransactionID = dbo. SET TRANSACTION ISOLATION LEVEL SERIALIZABLE Deadlock Avoidance When a database is stuck in a deadlock state, then it is better to avoid the database rather than aborting or restating the database. Here is what the stored procedure looks like. Unlike a conventional deadlock, a distributed deadlock is not detectable using the RDBMS lock manager. Looking at the XML properties we can notice the isolation level of both transactions is Serializable and that it’s the same object (stored procedure) causing the deadlock.
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