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sql-server - 减少 MS SQL 上更新查询时 PAGE 级别的死锁

转载 作者:太空狗 更新时间:2023-10-30 01:55:18 25 4
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在默认的“READ COMMITED”事务下,在平坦的普通表上,我有一个愚蠢的简单 SQL UPDATE 查询导致的一些有趣的死锁。

UPDATE table SET column=@P1 WHERE PK=@P2

PKvarchar(11),上面有一个聚集索引。表上没有触发器或表关系..等。

我做了一些检查,发现死锁发生在“PAGE”级别,而不是 ROW/记录级别。然后,我发现对于每个更新查询,它确实需要 100(或更多)个 PAGE 锁。 (这对我来说没有意义,因为我一次更新一行)

有什么办法可以防止死锁的发生吗?或者,如何在不使用游标的情况下减少单行更新所需的锁数?

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感谢您的建议。

我曾多次尝试重建索引,填充因子有高有低。我曾尝试让进程更新不同的位置/切片。但没有任何改善或恶化。

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我尝试了 SQL Server Profiler。我捕获了一些“Lock:Deadlock Chain”和“Lock:Deadlock”,但没有捕获到“死锁图”。双方都在读取提交、自动提交模式下进行简单的更新查询。

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

最佳答案

您有 2 个选项来减少锁定升级:

1) 添加 WITH (ROWLOCK) 提示以要求 sql server 采取更细粒度的锁(您的里程可能会有所不同:

UPDATE table WITH (ROWLOCK) SET column=@P1 WHERE PK=@P2; While PK varchar(11), has a clustered index on it. no tigger or table relation..etc on the table.

2) 以随机顺序更新行,这降低了行锁升级为页锁的可能性。

此外,确保该表上的索引是最新的通常可以减少锁定。如果您要进行大量插入,也可以保留填充因子(90 很好)。

关于sql-server - 减少 MS SQL 上更新查询时 PAGE 级别的死锁,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/321036/

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