I have verified the code that if autocommit is set to false on JDBC connection, jTDS driver in turn fires SET IMPLICIT TRANSACTIONS ON command to the database. Actually, we are using jTDS JDBC driver via Java Application to execute this queries.Thanks GilaMonster for detailed analysis. I would recommend removing the implicit transaction settings and explicitly creating and committing transactions where necessary, and allowing autocommit where they're not. I suspect that transactions are getting started, and not committed, and since locks taken from data modifications are held until the end of the transaction, you're having long-running transactions holding locks longer than expected, and hence causing deadlocks. This is not the default in SQL Server, so someone would have had to either set this in the application (session-level setting), or by SET IMPLICIT TRANSACTIONS ON That means that a transaction gets automatically started when a statement runs, and only gets committed when an explicit COMMIT TRANSACTION is run. Update set =+1 where = nvarchar(4000))update set =+1 where = Update set =-1 where = nvarchar(4000))update set =-1 where = ![]() Suspecting that table is getting locked instead of particular row, we even tried to disable escalation of locks at a table using following command but deadlocks persisted.ĪLTER TABLE Table_name SET ( LOCK_ESCALATION DISABLE).Same transaction is working with similar concurrent load in Oracle.Even inserts to the table becomes part of deadlock. Target Rows (Updates) in deadlocks are independent to each other so no question of one transaction waiting for other to relinquish lock.Herewith I have attached deadlock graph for reference. Issue : We are facing frequent deadlocks on this table. Table is getting updated on modification of status of workitem assigned to user. Following is the table structure used to maintain this summary. Requirement : Maintain summary of user’s workload in a table.
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