陈述:
对于数据库死锁，通常可以通过TRACE FLAG 1204、1205、1206，检查ERRORLOG里面的输出，和分析SQLTRACE的执行上下文判断死锁问题的来由。
TRACEON函数的第三个参数设置为-1，表示不单单针对当前connection，而是针对所有包括未来建立的connection。这样，才够完全，否则只是监视当前已经建立的数据库连接了。
执行下面的话可以把死锁记录到Errorlog中：
dbcc traceon (1204, 3605, -1)
go
dbcc tracestatus(-1)
go
得到的输出为：DBCC 执行完毕。如果 DBCC 输出了错误信息，请与系统管理员联系。
TraceFlag Status
--------- ------
1204 1
1205 1
3605 1
（所影响的行数为 3 行）
DBCC 执行完毕。如果 DBCC 输出了错误信息，请与系统管理员联系。
此后，你可以查看数据库的例行日志，每隔一段时间，数据库都会检查死锁，日志文本如下所示：2004-01-16 18:34:38.50 spid4 ----------------------------------
2004-01-16 18:34:38.50 spid4 Starting deadlock search 1976
2004-01-16 18:34:38.50 spid4 Target Resource Owner:
2004-01-16 18:34:38.50 spid4 ResType:LockOwner Stype:'OR' Mode: U SPID:55 ECID:0 Ec:(0xAA577570) Value:0x4c25cba0
2004-01-16 18:34:38.50 spid4 Node:1 ResType:LockOwner Stype:'OR' Mode: U SPID:55 ECID:0 Ec:(0xAA577570) Value:0x4c25cba0
2004-01-16 18:34:38.50 spid4 Node:2 ResType:LockOwner Stype:'OR' Mode: U SPID:71 ECID:0 Ec:(0xABF07570) Value:0x9bd0ba00
2004-01-16 18:34:38.50 spid4
2004-01-16 18:34:38.50 spid4 -- next branch --
2004-01-16 18:34:38.50 spid4 Node:2 ResType:LockOwner Stype:'OR' Mode: U SPID:71 ECID:0 Ec:(0xABF07570) Value:0x9bd0ba00
2004-01-16 18:34:38.50 spid4
2004-01-16 18:34:38.50 spid4
2004-01-16 18:34:38.50 spid4 End deadlock search 1976 ... a deadlock was not found.
2004-01-16 18:34:38.50 spid4 ----------------------------------
以下实际检测到死锁的日志输出，来自于一份非常棒的讲义“Log Shipping in SQL Server 2000.ppt”，作者是Ron Talmage：Deadlock encountered .... Printing deadlock information Wait-for graph Node:1KEY: 7:1977058079:1 (f600d547433a) CleanCnt:1 Mode: X Flags: 0x0 Grant List:: Owner:0x19090e20 Mode: X Flg:0x0 Ref:0 Life:02000000 SPID:54 ECID:0 SPID: 54 ECID: 0 Statement Type: SELECT Line #: 1 Input Buf: Language Event: Select * From Authors Requested By: ResType:LockOwner Stype:'OR' Mode: S SPID:53 ECID:0 Ec:(0x19c5d530) Value:0x19090dc0 Cost:(0/114) Node:2KEY: 7:1977058079:1 (f5006f164aa3) CleanCnt:1 Mode: X Flags: 0x0 Grant List:: Owner:0x19091000 Mode: X Flg:0x0 Ref:0 Life:02000000 SPID:53 ECID:0 SPID: 53 ECID: 0 Statement Type: SELECT Line #: 1 Input Buf: Language Event: Select * From Authors Requested By: ResType:LockOwner Stype:'OR' Mode: S SPID:54 ECID:0 Ec:(0x19dc3530) Value:0x19091180 Cost:(0/114)Victim Resource Owner: ResType:LockOwner Stype:'OR' Mode: S SPID:54 ECID:0 Ec:(0x19dc3530) Value:0x19091180 Cost:(0/114)