Explanation When deadlocks occur, trace flag 1204 and trace flag 1222 return information that is captured in the SQL Server error log. Trace flag 1204 reports deadlock information formatted by each node involved in the deadlock. Trace flag 1222 formats deadlock information, first by processes and then by resources. The output format for Trace Flag 1222 only returns information in an XML-like format. References: https://technet.microsoft.com/en-us/library/ms178104(v=sql.105).aspx