Click here to monitor SSC SQLServerCentral is supported by Red
Gate Software Ltd. Log in  ::  Register  ::  Not logged in  A
Deadlock Occurrence and Resolution  By Praveen Voleti, (first
published: 2009/02/03)   An upgrade was performed at my company
recently to the application code on the SQL Server, which
involved basically the addition of columns to few tables. After
the upgrade, the customer started facing severe deadlocks.
Around 8 out of 10 transactions were getting deadlocked and were
failing.  Steps Taken in resolving the deadlocks:  I will walk
through the steps we took to determine what was causing the
deadlock and resolve the issue.  1. First I enabled the trace
flag 1204 on the server to capture the deadlock details in the
error log with the command listed below:  DBCC traceon(1204,-1)
Next I confirmed that the trace was enabled with the below
command:  DBCC Tracestatus(-1)  The output shown below indicated
that the trace flag 1204 was enabled.  TraceFlag Status Global
Session 1204      1      1