参考文章：
简单的说：
1.死锁发生前，打开开关：
DBCC Traceon (1204,-1)
DBCC Traceon (1222,-1)
2.等待死锁发生
3.查询死锁信息：
Use Master
SELECT
xed.value('@timestamp', 'datetime') as Creation_Date,
xed.query('.') AS Extend_Event
FROM
(
SELECT CAST([target_data] AS XML) AS Target_Data
FROM sys.dm_xe_session_targets AS xt
INNER JOIN sys.dm_xe_sessions AS xs
ON xs.address = xt.event_session_address
WHERE xs.name = N'system_health'
AND xt.target_name = N'ring_buffer'
) AS XML_Data
CROSS APPLY Target_Data.nodes('RingBufferTarget/event[@name="xml_deadlock_report"]') AS XEventData(xed)
ORDER BY Creation_Date DESC