我的简单测试表明，我可以在 2 个表上获取排他锁，或者推迟获取任一表上的锁，直到可以使用如下查询一次获取两者：
SELECT AutoKey, OnHand FROM ONNM(XLOCK) CROSS JOIN OITM(XLOCK)
WHERE ObjectCode IN ('20', '10000048') AND ItemCode = @ItemCode
关键特性是用于在单个查询中包含多个表的 CROSS JOIN。我确认如果 OITM 行上已经存在另一个事务中 @ItemCode 的排他锁，那么该语句不会在 ONNM 上引入任何锁，直到它可以获取两个锁。但是，在更复杂的完整测试运行中，SQL 探查器返回一些相互冲突的信息。我已将 SQL 分析器结果导入表并执行以下查询：
select rownum, e.name, EventClass, TextData, SPID, ClientProcessID from #pmit t
join sys.trace_events e on t.EventClass = e.trace_event_id
where rownum between 275799 and 546130
and (TextData LIKE '(ca73a6396124)' or TextData LIKE '(36fa3e654c8f)'
or TextData LIKE '%(XLOCK)%' or TextData LIKE '%DeadLock%')
order by rownum
这些是我得到的结果：
Row | Event | SPID | Text
275799 | SP:StmtStarting | 99 | SELECT AutoKey, OnHand FROM ONNM(XLOCK) CROSS JOIN OITM(XLOCK) WHERE ObjectCode IN ('20', '10000048') AND ItemCode = @ItemCode
304781 | Lock:Acquired | 139 | (36fa3e654c8f)
305365 | Lock:Acquired | 139 | (36fa3e654c8f)
351093 | Lock:Acquired | 139 | (ca73a6396124)
468768 | Lock:Released | 13 | (ca73a6396124)
470912 | Lock:Released | 13 | (36fa3e654c8f)
470922 | Lock:Acquired | 164 | (36fa3e654c8f)
470928 | Lock:Released | 164 | (36fa3e654c8f)
470971 | Lock:Acquired | 99 | (36fa3e654c8f)
471013 | RPC:Completed | 99 | exec sp_executesql N'SELECT AutoKey, OnHand FROM ONNM(XLOCK) CROSS JOIN OITM(XLOCK) WHERE ObjectCode IN (''20'', ''10000048'') AND ItemCode = @ItemCode',N'@ItemCode nvarchar(3)',@ItemCode=N'FX1'
490843 | SP:StmtStarting | 78 | SELECT AutoKey, OnHand FROM ONNM(XLOCK) CROSS JOIN OITM(XLOCK) WHERE ObjectCode IN ('20', '10000048') AND ItemCode = @ItemCode
490848 | Lock:Acquired | 78 | (ca73a6396124)
495391 | Lock:Acquired | 114 | (36fa3e654c8f)
495396 | Lock:Acquired | 114 | (36fa3e654c8f)
542738 | Lock:Deadlock Chain | 6 | Deadlock Chain SPID = 78 (36fa3e654c8f)
545746 | Lock:Deadlock Chain | 6 | Deadlock Chain SPID = 154 (36fa3e654c8f)
545769 | Lock:Deadlock Chain | 6 | Deadlock Chain SPID = 114 (ca73a6396124)
545982 | Lock:Deadlock | 78 | (36fa3e654c8f)
545985 | RPC:Completed | 78 | exec sp_executesql N'SELECT AutoKey, OnHand FROM ONNM(XLOCK) CROSS JOIN OITM(XLOCK) WHERE ObjectCode IN (''20'', ''10000048'') AND ItemCode = @ItemCode',N'@ItemCode nvarchar(3)',@ItemCode=N'FC3'
545990 | Lock:Released | 78 | (ca73a6396124)
545998 | Lock:Acquired | 114 | (ca73a6396124)
546130 | Deadlock graph | 17 | (See below)
死锁图如下：
<deadlock-list>
<deadlock victim="process5e3ae08">
<process-list>
<process id="process5e3ae08" taskpriority="0" logused="0" waitresource="KEY: 6:72057598620205056 (36fa3e654c8f)" waittime="9507" ownerId="513854688" transactionname="user_transaction" lasttranstarted="2012-06-28T13:38:54.463" XDES="0x1bbf9b950" lockMode="RangeX-X" schedulerid="6" kpid="13248" status="suspended" spid="78" sbid="0" ecid="0" priority="0" trancount="1" lastbatchstarted="2012-06-28T13:38:54.483" lastbatchcompleted="2012-06-28T13:38:54.463" clientapp=".Net SqlClient Data Provider" hostname="PMIUSRSTL00013" hostpid="3180" loginname="RICFSE01SAPB1" isolationlevel="serializable (4)" xactid="513854688" currentdb="6" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056">
<executionStack>
<frame procname="adhoc" line="1" stmtstart="46" sqlhandle="0x02000000151c651e3c8b4437ee414cefdbc46b70aceca960"> SELECT AutoKey, OnHand FROM ONNM(XLOCK) CROSS JOIN OITM(XLOCK) WHERE ObjectCode IN ('20', '10000048') AND ItemCode = @ItemCode </frame>
<frame procname="unknown" line="1" sqlhandle="0x000000000000000000000000000000000000000000000000"> unknown </frame>
</executionStack>
<inputbuf> (@ItemCode nvarchar(3))SELECT AutoKey, OnHand FROM ONNM(XLOCK) CROSS JOIN OITM(XLOCK) WHERE ObjectCode IN ('20', '10000048') AND ItemCode = @ItemCode </inputbuf>
</process>
<process id="process5e45048" taskpriority="0" logused="0" waitresource="KEY: 6:72057598620205056 (36fa3e654c8f)" waittime="12866" ownerId="513845303" transactionname="SELECT" lasttranstarted="2012-06-28T13:38:28.463" XDES="0x80048e50" lockMode="S" schedulerid="7" kpid="12772" status="suspended" spid="154" sbid="0" ecid="0" priority="0" trancount="0" lastbatchstarted="2012-06-28T13:38:28.390" lastbatchcompleted="2012-06-28T13:38:28.380" lastattention="2012-06-28T13:38:27.927" clientapp="TagClerkService" hostname="PMIUSRSTW00008" hostpid="2772" loginname="RICFSE01SAPB1" isolationlevel="read committed (2)" xactid="513845303" currentdb="6" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056">
<executionStack>
<frame procname="adhoc" line="1" sqlhandle="0x020000000d86e30171762b464b35e0923de532c497188b81"> SELECT T0.* FROM [dbo].[ONNM] T0 </frame>
</executionStack>
<inputbuf> SELECT T0.* FROM [dbo].[ONNM] T0 </inputbuf>
</process>
<process id="process5e31708" taskpriority="0" logused="25240" waitresource="KEY: 6:72057597517103104 (ca73a6396124)" waittime="2031" ownerId="513831818" transactionguid="0xdefde99023405d4a96d101faac79ef96" transactionname="user_transaction" lasttranstarted="2012-06-28T13:38:19.237" XDES="0xd68df950" lockMode="RangeS-S" schedulerid="5" kpid="11564" status="suspended" spid="114" sbid="0" ecid="0" priority="0" trancount="1" lastbatchstarted="2012-06-28T13:38:58.560" lastbatchcompleted="2012-06-28T13:38:58.490" lastattention="2012-06-28T12:48:33.060" clientapp="TagClerkService" hostname="PMIUSRSTL00011" hostpid="2908" loginname="RICFSE01SAPB1" isolationlevel="serializable (4)" xactid="513831818" currentdb="6" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056">
<executionStack>
<frame procname="adhoc" line="1" stmtstart="24" sqlhandle="0x02000000a329a30eb1319f2df684296f889a1613a585b3a0"> SELECT ISNULL(a.U_FSE_ApplicationUsr,a.UserSign) ,a.DocNum ,b.LineNum ,f.IsLotTraced ,h.LotNumber ,b.WhsCode ,n.Bin ,g.Quantity ,b.LineTotal ,i.OnTimeDeliveryDaysEarly ,i.OnTimeDeliveryDaysLate ,i.ReceiptVarianceUnderAllowed ,i.ReceiptVarianceOverAllowed ,k.ItemCode ,d.Revision ,a.Comments ,e.RolledMaterialCost ,e.RolledLaborCost ,e.RolledVariableOverheadCost ,e.RolledFixedOverheadCost ,e.RolledOutsideCost ,ISNULL(c.Quantity, c2.Quantity) ,c.DocumentLineDetailKey /* TODO: Handle serial numbers for blanket deliveries */ ,ISNULL(c.InventoryCode, c2.InventoryCode) ,k.InvntryUom ,r.Resource ,p.ItemName ,CASE WHEN m.MOKey IS NULL THEN NULL ELSE b.U_FSE_STypeItemQty END ,a.DocDate FROM OPDN a LEFT JOIN PDN1 b ON a.DocEntry=b.DocEntry LEFT JOIN FSE_PurchaseGoodsReceiptLineDetail c ON (b.DocEntry=c.DocumentKey and b.LineNum=c.DocumentLineKey) LEFT JOIN FSE_PurchaseGoodsReceiptDeliveryLineDetail c2 ON (b.DocEntry=c2.DocumentKey and b.LineNum=c2.DocumentLineKey) LEFT JOIN FSE_MO m ON m.DocumentNumber = b.U_FSE_MONumbe </frame>
<frame procname="unknown" sqlhandle="0x000000000000000000000000000000000000000000000000"> unknown </frame>
<frame procname="FSDB00.dbo.SBO_SP_TransactionNotification" line="25" stmtstart="1588" stmtend="2032" sqlhandle="0x030006000a73d75dfe95d60059a000000100000000000000"> exec usp_FSE_HandleSBONotification @object_type, @transaction_type, @num_of_cols_in_key, @list_of_key_cols_tab_del, @list_of_cols_val_tab_del, @error out, @error_message out -- keep this on one line --PMI DataTransfer </frame>
<frame procname="adhoc" line="1" sqlhandle="0x01000600fd116804e00371a5000000000000000000000000"> EXECUTE SBO_SP_TransactionNotification N'20',N'A',1,N'DocEntry',N'134138' </frame>
</executionStack>
<inputbuf> EXECUTE SBO_SP_TransactionNotification N'20',N'A',1,N'DocEntry',N'134138' </inputbuf>
</process>
</process-list>
<resource-list>
<keylock hobtid="72057598620205056" dbid="6" objectname="FSDB00.dbo.ONNM" indexname="ONNM_PRIMARY" id="lock1aa7d9880" mode="RangeX-X" associatedObjectId="72057598620205056">
<owner-list/>
<waiter-list>
<waiter id="process5e3ae08" mode="RangeX-X" requestType="wait"/>
</waiter-list>
</keylock>
<keylock hobtid="72057598620205056" dbid="6" objectname="FSDB00.dbo.ONNM" indexname="ONNM_PRIMARY" id="lock1aa7d9880" mode="RangeX-X" associatedObjectId="72057598620205056">
<owner-list>
<owner id="process5e31708" mode="RangeX-X"/>
</owner-list>
<waiter-list>
<waiter id="process5e45048" mode="S" requestType="wait"/>
</waiter-list>
</keylock>
<keylock hobtid="72057597517103104" dbid="6" objectname="FSDB00.dbo.OITM" indexname="OITM_PRIMARY" id="lock215ce6980" mode="X" associatedObjectId="72057597517103104">
<owner-list>
<owner id="process5e3ae08" mode="X"/>
</owner-list>
<waiter-list>
<waiter id="process5e31708" mode="RangeS-S" requestType="wait"/>
</waiter-list>
</keylock>
</resource-list>
</deadlock>
</deadlock-list>
我的问题是，为什么 SPID 78 有可能（是否正常）获得对 OITM（ca73a6396124）的锁定（如果我没记错的话，它恰好代表 ItemCode FC1）即使它无法获得对 ONNM 的锁定（36fa3e654c8f） . 我对 SQL 语句获得全或全锁的假设是不正确的吗？如果 ONNM 锁的持有者是在另一个进程中包含多个连接的事务中的不同连接上的共享锁，它是否不成立？（我认为 SPID 99 是与 SPID 114 在同一进程中的另一个连接。）
这似乎是一个非常复杂的问题。我不知道是否有更好的方法来避免死锁或找出这里发生的事情。