在默認的「READ COMMITED」事務下,在平坦的普通表上,有一個愚蠢的簡單SQL UPDATE查詢導致了一些有趣的死鎖。在MS SQL上更新查詢時減少PAGE級別上的死鎖
更新表SET列= @ P1 WHERE PK = @ P2; 雖然PK varchar(11),它有一個聚集索引。 桌子上沒有觸發器或表格關係..等等。
我做了一些檢查,發現死鎖發生在「PAGE」級別,而不是ROW /記錄級別。 然後,我發現對於每個更新查詢,它需要100個(和更多)PAGE鎖。 (這對我沒有意義,因爲我一次更新一行)
有沒有什麼辦法可以防止死鎖的發生?或者,如何在不使用光標的情況下減少單個行更新所需的鎖定數量?
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感謝您的建議。
我曾嘗試重建索引幾次,填充因子高低。我試圖讓流程更新不同的位置/切片。但沒有什麼改善或最壞的。
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我試過了SQL Server Profiler。我捕獲了一些「鎖:死鎖鏈」和「鎖:死鎖」, 但沒有「死鎖圖」被捕獲。雙方都在讀取提交的自動提交模式下執行簡單的更新查詢。
Lock:Deadlock Chain 17887475 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange Lock:Deadlock Chain 17887476 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:438102 265006271 0 0X56AF060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887477 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange Lock:Deadlock Chain 17887478 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 54 1:426206 265006240 0 0XDE80060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887479 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:426206 265006271 0 0XDE80060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887480 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange Lock:Deadlock Chain 17887481 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 54 1:426066 265006240 0 0X5280060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887482 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:426066 265006271 0 0X5280060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887483 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange Lock:Deadlock Chain 17887484 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:425614 265006271 0 0X8E7E060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887485 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange Lock:Deadlock Chain 17887486 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:426687 265006271 0 0XBF82060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887487 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange
Lock:Deadlock Chain 17887488 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:425392 265006271 0 0XB07D060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887489 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange
Lock:Deadlock Chain 17887491 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange
Lock:Deadlock Chain 17887493 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange
Lock:Deadlock Chain 17887494 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:435792 265006271 0 0X50A6060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock Chain 17887495 1 0X01 4 myserver 2008-11-28 10:16:46.210 Parallel query worker thread was involved in a deadlock 0 971497 102 - Resource type Exchange
Lock:Deadlock Chain 17887496 1 0X01 4 myserver 2008-11-28 10:16:46.210 Deadlock Chain SPID = 209 1:438206 265006271 0 0XBEAF060001000000000000001B0006 27 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971497 101 - Resource type Lock
Lock:Deadlock 17887497 myuser 0XCD85FBB269700B4AA2F4E8579D118999 209 myserver myuser 2008-11-28 10:16:45.930 1:426206 265006271 myapps 0 0XDE80060001000000000000001B0006 123 27 281 2008-11-28 10:16:46.210 myclient 0 - LOCK 4 - U 0 72057594040352768 1 - TRANSACTION 0 6 - PAGE mydatabase 971498
這是最奇怪的部分,另一方做完全相同的查詢,完整的另一個主鍵。 – 2008-11-26 16:38:15
而且我甚至會斷開/重新連接,以確保沒有任何隱藏的鎖/事務。 – 2008-11-26 16:39:36