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  • 死锁的进程

    杀掉那些死锁的进程

     

      前些天,同事遇到一个死锁的问题,又想起三年前面试的时候问的一个with(nolock)相关的问题,一下子不知道怎么解锁,走过去看看,一下子不知道怎么写,忙活了一会,弄出个东东,核心主要是视图sys.SysProcesses,它源自于系统表sysprocesses,前者是微软推荐的用法,因为后者在未来SQL Server版本中可能会被隐藏。视图字段含义见这里。然后是kill 命令,它加上进程id就可以杀掉相应进程,它的简单用法如下:

    use Test
    go
    -- 列出所有进程信息
    EXEC sp_who2
    go

    -- 执行杀掉进程命令
    KILL 29
    go

    复制代码
    1 use Test
    2 go
    3 -- 列出所有进程信息
    4 EXEC sp_who2
    5 go
    6 
    7 -- 执行杀掉进程命令
    8 KILL 29
    9 go
    复制代码

     准备工作:

    CREATE TABLE TestDead
    (
    id INT IDENTITY(1,1) PRIMARY KEY,
    name NVARCHAR(10) NOT NULL
    )
    GO

    CREATE TABLE TestDead2
    (
    id INT IDENTITY(1,1) PRIMARY KEY,
    name NVARCHAR(10) NOT NULL
    )
    GO

    INSERT INTO TestDead(name)
    VALUES ('name01'),
    ('name02'),
    ('name03')
    GO

    INSERT INTO TestDead2(name)
    VALUES ('name01'),
    ('name02'),
    ('name03')
    GO

    BEGIN TRAN -- 打开一个更新事务,不提交, 锁住第一个表

    UPDATE TestDead SET name = 'nameXX' WHERE id = 1

    GO


    BEGIN TRAN --开始一个事务,不提交,锁住第二个表

    UPDATE TestDead2 SET name = 'nameXX' WHERE id = 1

    GO

    复制代码
     1 CREATE TABLE  TestDead
     2 (
     3     id INT IDENTITY(1,1) PRIMARY KEY,
     4     name NVARCHAR(10) NOT NULL
     5 )
     6 GO
     7 
     8 CREATE TABLE  TestDead2
     9 (
    10     id INT IDENTITY(1,1) PRIMARY KEY,
    11     name NVARCHAR(10) NOT NULL
    12 )
    13 GO
    14 
    15 INSERT INTO TestDead(name)
    16 VALUES ('name01'), 
    17        ('name02'),
    18        ('name03')
    19 GO
    20 
    21 INSERT INTO TestDead2(name)
    22 VALUES ('name01'), 
    23        ('name02'),
    24        ('name03')
    25 GO
    26 
    27 BEGIN TRAN  -- 打开一个更新事务,不提交, 锁住第一个表
    28 
    29 UPDATE TestDead SET name = 'nameXX' WHERE id = 1
    30 
    31 GO
    32 
    33 
    34 BEGIN TRAN  --开始一个事务,不提交,锁住第二个表
    35 
    36 UPDATE TestDead2 SET name = 'nameXX' WHERE id = 1
    37 
    38 GO
    复制代码

    创建了表之后,开始一个更新数据的事务并锁住了表,然后新建多个查询窗口,在各个不同窗口中,分别执行下面两条语句:

    -- 查询第一个表

    select * from TestDead


    -- 查询第二个表

    select * from TestDead2

    复制代码
    1 -- 查询第一个表
    2 
    3 select * from TestDead
    4 
    5 
    6 -- 查询第二个表
    7 
    8 select * from TestDead2
    复制代码

    现在由于表被锁住,是查询不出数据,除非在后面加上 with(nolock),如:

    1 select * from TestDead2 with(nolock)
    1 select * from TestDead2 with(nolock)

    列出并杀掉那些死锁的进程:

    -- =============================================
    -- Author: Mike Deng
    -- Create date: 2014/05/14
    -- Description: 杀掉死锁进程
    -- =============================================

    DECLARE @toKill BIT = 0 --0 或 NULL 只显示, 1.杀掉

    BEGIN
    DECLARE @sql NVARCHAR(MAX);
    DECLARE @fromSql NVARCHAR(MAX);

    -- 查询出所有死锁和与被阻塞的进程
    SET @fromSql = '
    DECLARE @cmd NVARCHAR(MAX);
    ;WITH CTE as(
    SELECT DISTINCT Type = ''死锁的进程''
    , a.spid
    , blockId = 0
    , DBName = DB_NAME(a.dbid)
    , a.HostName
    , ProgramName = a.Program_Name
    , Dead = 1
    FROM SYS.SYSPROCESSES a JOIN
    SYS.SYSPROCESSES as b ON a.spid = b.blocked
    WHERE a.blocked = 0
    UNION ALL
    SELECT DISTINCT Type = ''被阻塞的进程''
    , a.spid
    , blockId = a.blocked
    , DBName = DB_NAME(a.dbid)
    , a.HostName
    , ProgramName = a.Program_Name
    , Dead = 0
    FROM SYS.SYSPROCESSES a WHERE blocked <> 0
    ) '

    -- 根据传入的值,决定是否删除
    IF(ISNULL(@toKill, 0) = 1) --如果等于 1,则杀掉
    BEGIN
    SET @sql = @fromSql
    + 'SELECT @cmd = (
    SELECT ('' KILL '' + LTRIM(str(spid))) FROM cte WHERE dead = 1
    FOR XML PATH('''')
    )

    IF(ISNULL(@cmd, '''') <> '''')
    BEGIN
    EXEC (@cmd);
    PRINT ''已执行kill死锁命令【'' + @cmd + ''】, 锁已解除'';
    END
    ELSE IF(@@RowCount = 0)
    BEGIN
    PRINT ''未发现死锁, 不能杀掉'';
    END'
    END
    ELSE
    BEGIN -- 显示所有死锁与被阻塞的进程
    SET @sql = @fromSql + ', cte2 AS( SELECT * FROM cte WHERE Dead = 1
    UNION ALL
    SELECT k.* FROM cte AS k JOIN
    cte2 AS p ON k.blockId = p.spid
    )
    SELECT * FROM cte2 ORDER BY blockId';
    END

    EXEC SP_EXECUTESQL @sql
    END

    复制代码
     1 -- =============================================
     2 -- Author:      Mike Deng
     3 -- Create date: 2014/05/14
     4 -- Description: 杀掉死锁进程
     5 -- =============================================
     6 
     7 DECLARE    @toKill BIT = 0  --0 或 NULL 只显示, 1.杀掉
     8 
     9 BEGIN
    10     DECLARE @sql NVARCHAR(MAX);
    11     DECLARE @fromSql NVARCHAR(MAX);
    12 
    13     -- 查询出所有死锁和与被阻塞的进程
    14     SET @fromSql = '
    15     DECLARE @cmd NVARCHAR(MAX);
    16     ;WITH CTE as(
    17           SELECT DISTINCT Type = ''死锁的进程''
    18             , a.spid
    19             , blockId = 0
    20             , DBName = DB_NAME(a.dbid)
    21             , a.HostName
    22             , ProgramName = a.Program_Name
    23             , Dead = 1
    24           FROM SYS.SYSPROCESSES a JOIN 
    25                 SYS.SYSPROCESSES as b ON a.spid = b.blocked
    26                       WHERE a.blocked = 0
    27             UNION ALL
    28         SELECT DISTINCT  Type = ''被阻塞的进程''
    29             , a.spid
    30             , blockId = a.blocked
    31             , DBName = DB_NAME(a.dbid)
    32             , a.HostName
    33             , ProgramName = a.Program_Name
    34             , Dead = 0
    35         FROM SYS.SYSPROCESSES a WHERE blocked <> 0
    36     )  '
    37 
    38     -- 根据传入的值,决定是否删除
    39     IF(ISNULL(@toKill, 0) = 1)  --如果等于 1,则杀掉
    40         BEGIN
    41             SET @sql = @fromSql
    42                 + 'SELECT @cmd =  (
    43                         SELECT  ('' KILL '' + LTRIM(str(spid))) FROM cte WHERE dead = 1
    44                             FOR XML PATH('''')
    45                     )
    46 
    47                     IF(ISNULL(@cmd, '''') <> '''')
    48                         BEGIN
    49                             EXEC (@cmd);
    50                             PRINT ''已执行kill死锁命令【'' + @cmd + ''】, 锁已解除'';
    51                         END 
    52                     ELSE IF(@@RowCount = 0)
    53                         BEGIN
    54                             PRINT ''未发现死锁, 不能杀掉'';
    55                         END'
    56         END
    57     ELSE
    58         BEGIN   -- 显示所有死锁与被阻塞的进程
    59             SET @sql = @fromSql + ', cte2 AS( SELECT * FROM cte WHERE Dead = 1
    60                                                     UNION ALL
    61                                               SELECT k.* FROM cte AS k JOIN 
    62                                                 cte2 AS p ON k.blockId = p.spid
    63                                         )
    64                                         SELECT * FROM cte2 ORDER BY blockId';
    65         END
    66 
    67     EXEC SP_EXECUTESQL @sql
    68 END
    复制代码

    查询结果:

    设置参数 @toKill = 1,杀掉它们。

    完工!

     
     
     
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  • 原文地址:https://www.cnblogs.com/Leo_wl/p/3731121.html
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