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use master
go
create procedure sp_who_lock
as
begin
declare @spid int,@bl int,
@intTransactionCountOnEntry int,
@intRowcount int,
@intCountProperties int,
@intCounter int create table #tmp_lock_who (
id int identity(1,1),
spid smallint,
bl smallint)
IF @@ERROR<>0 RETURN @@ERROR
insert into #tmp_lock_who(spid,bl) select 0 ,blocked
from (select * from sysprocesses where blocked>0 ) a
where not exists(select * from (select * from sysprocesses where blocked>0 ) b
where a.blocked=spid)
union select spid,blocked from sysprocesses where blocked>0 IF @@ERROR<>0 RETURN @@ERROR
-- 找到临时表的记录数
select @intCountProperties = Count(*),@intCounter = 1
from #tmp_lock_who
IF @@ERROR<>0 RETURN @@ERROR
if @intCountProperties=0
select '现在没有阻塞和死锁信息' as message-- 循环开始
while @intCounter <= @intCountProperties
begin
-- 取第一条记录
select @spid = spid,@bl = bl
from #tmp_lock_who where Id = @intCounter
begin
if @spid =0
select '引起数据库死锁的是: '+ CAST(@bl AS VARCHAR(10)) + '进程号,其执行的SQL语法如下'
else
select '进程号SPID:'+ CAST(@spid AS VARCHAR(10))+ '被' + '进程号SPID:'+ CAST(@bl AS VARCHAR(10)) +'阻塞,其当前进程执行的SQL语法如下'
DBCC INPUTBUFFER (@bl )
end -- 循环指针下移
set @intCounter = @intCounter + 1
enddrop table #tmp_lock_whoreturn 0
end
杀死锁和进程如何去手动的杀死进程和锁?最简单的办法,重新启动服务。但是这里要介绍一个存储过程,通过显式的调用,可以杀死进程和锁。use master
goif exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[p_killspid]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
drop procedure [dbo].[p_killspid]
GOcreate proc p_killspid
@dbname varchar(200) --要关闭进程的数据库名
as
declare @sql nvarchar(500)
declare @spid nvarchar(20) declare #tb cursor for
select spid=cast(spid as varchar(20)) from master..sysprocesses where dbid=db_id(@dbname)
open #tb
fetch next from #tb into @spid
while @@fetch_status=0
begin
exec('kill '+@spid)
fetch next from #tb into @spid
end
close #tb
deallocate #tb
go--用法
exec p_killspid 'newdbpy'
查看锁信息如何查看系统中所有锁的详细信息?在企业管理管理器中,我们可以看到一些进程和锁的信息,这里介绍另外一种方法。--查看锁信息
create table #t(req_spid int,obj_name sysname)declare @s nvarchar(4000)
,@rid int,@dbname sysname,@id int,@objname sysnamedeclare tb cursor for
select distinct req_spid,dbname=db_name(rsc_dbid),rsc_objid
from master..syslockinfo where rsc_type in(4,5)
open tb
fetch next from tb into @rid,@dbname,@id
while @@fetch_status=0
begin
set @s='select @objname=name from ['+@dbname+']..sysobjects where id=@id'
exec sp_executesql @s,N'@objname sysname out,@id int',@objname out,@id
insert into #t values(@rid,@objname)
fetch next from tb into @rid,@dbname,@id
end
close tb
deallocate tbselect 进程id=a.req_spid
,数据库=db_name(rsc_dbid)
,类型=case rsc_type when 1 then 'NULL 资源(未使用)'
when 2 then '数据库'
when 3 then '文件'
when 4 then '索引'
when 5 then '表'
when 6 then '页'
when 7 then '键'
when 8 then '扩展盘区'
when 9 then 'RID(行 ID)'
when 10 then '应用程序'
end
,对象id=rsc_objid
,对象名=b.obj_name
,rsc_indid
from master..syslockinfo a left join #t b on a.req_spid=b.req_spidgo
drop table #t参考
我都不看得眼花,SQL77
那个是不是说在select的时候加上(rowlock)?
这样就可以防止表锁吗?
insert into BFS_BusinessInfo with(rowlock) values (.....)
这个语句是不是把表的锁机制改为行级锁啊,
这样是不是可以避免表锁的呢?
除非属于临时表锁,否则意向锁、行锁和页锁都将计入升级统计中。当特定表上意向锁、行锁和页锁的总数超出升级阈值时,就会进行升级。
您可以通过设置锁升级阈值来控制每个会话的锁升级,如以下代码示例所示:SET LOCK_ESCALATION 1000; 此设置影响数据库中的所有表。默认值为 100。
原来的存储过程里就是没有 with(rowlock)这个语句,
所以当有两笔数据同时过来插入数据库时,
总会有其中的一笔是因为死锁而处理失败,
另外一笔处理成功,
我就想是不是因为sqlserver是默认的表锁,当有多笔数据过来插入数据库时,其中两笔同时插入,其中一笔插入时,启用了表锁,所以另外一笔就失败了?
我加个with(rowlock)可不可以解决这个问题呢?USE BFSDB
IF EXISTS (SELECT * FROM sysobjects WHERE type = 'P' AND name = 'up_InsertBFSBusinessInfo')
BEGIN
DROP Procedure up_InsertBFSBusinessInfo
ENDGO/******************************************************************************
** File: up_InsertBFSBusinessInfo.Sql
** Name: up_InsertBFSBusinessInfo
** Desc: 添加CPC请求的业务信息
** Return Value:
**
** Auth:
** Date: 2008-04-23
*******************************************************************************
** Change History
*******************************************************************************
** Date: Author: Description:
** -------- -------- ---------------------------------------
**
*******************************************************************************/
CREATE Procedure up_InsertBFSBusinessInfo
(
@BusinessGuid varchar(50) , -- 系统内部编号
@CPCXmlData text , -- CPC报文数据
@TransCode varchar(4) , -- 交易码
@InitBranchId varchar(4) , -- 流程发起机构号
@InitUserId varchar(8) , -- 流程发起柜员号
@TransactionDate varchar(20) , -- 当前日期
@BusinessId varchar(20) , -- 业务流水号
@BusinessType varchar(5) , -- 业务种类
@BusinessInitBranchId varchar(4) , -- 业务发起机构号
@ExchangeDate varchar(8) , -- 交换日期
@ExchangeRound varchar(1) , -- 交换场次
@ImageFilePath varchar(100) , -- 影像路径
@ImageFileName varchar(1000) , -- 影像名称
@CurrencyType varchar(3) , -- 币种
@VoucherType varchar(2), -- 票据种类
@VoucherNo varchar(12) , -- 票据号码
@PayeeAccountNo varchar(32) , -- 收款人账号
@PayeeFullName varchar(62) , -- 收款人名称
@PayerAccountNo varchar(32) , -- 出票人账号
@PayerFullName varchar(62) , -- 出票人名称
@Amount decimal(18,2) , -- 金额
@VoucherIssueDate varchar(8) , -- 出票日期
@PaymentCode varchar(16) , -- 支付密码
@ExchangeBranchId varchar(12) , -- 提出行行号
@ExchangeInBranchNo varchar(12) , -- 提回行行号
@PaperFlag varchar(1) , -- 纸票标志
@Comments varchar(60) , -- 注释
@MaxEndorseIndex varchar(3) , -- 最大粘单索引
@SopSSN varchar(12) , -- 柜员流水号
@ProcessBeginTime datetime, --处理开始时间
@ProcessEndTime datetime, --处理结束时间
@ProcessStatus int , -- 处理状态
@Re text -- 描述
)AS
BEGIN TRANSACTION Tran_BFSdeclare @n int
select @n=count(*) from BFS_BusinessInfo with (nolock) where BusinessId= @BusinessIdif (@n>0)
begin
--删除已存在的影像存储信息
delete from BFS_ImageStoreInfo
where BusinessGuid=(
select BusinessGuid from BFS_BusinessInfo with (nolock)
where BusinessId= @BusinessId )
--删除已存在的业务信息
delete from BFS_BusinessInfo
where BusinessId=@BusinessId
end--添加一条新记录insert into BFS_BusinessInfo
(
BusinessGuid,
CPCXmlData,
TransCode ,
InitBranchId,
InitUserId ,
TransactionDate ,
BusinessId ,
BusinessType ,
BusinessInitBranchId ,
ExchangeDate ,
ExchangeRound ,
ImageFilePath ,
ImageFileName,
CurrencyType,
VoucherType ,
VoucherNo ,
PayeeAccountNo,
PayeeFullName ,
PayerAccountNo,
PayerFullName ,
Amount,
VoucherIssueDate ,
PaymentCode ,
ExchangeBranchId ,
ExchangeInBranchNo ,
PaperFlag ,
Comments ,
MaxEndorseIndex ,
SopSSN ,
ProcessBeginTime,
ProcessEndTime,
ProcessStatus,
Re )
values
(
@BusinessGuid,
@CPCXmlData,
@TransCode ,
@InitBranchId,
@InitUserId ,
@TransactionDate ,
@BusinessId ,
@BusinessType ,
@BusinessInitBranchId ,
@ExchangeDate ,
@ExchangeRound ,
@ImageFilePath ,
@ImageFileName,
@CurrencyType,
@VoucherType ,
@VoucherNo ,
@PayeeAccountNo,
@PayeeFullName ,
@PayerAccountNo,
@PayerFullName ,
@Amount,
@VoucherIssueDate ,
@PaymentCode ,
@ExchangeBranchId ,
@ExchangeInBranchNo ,
@PaperFlag ,
@Comments ,
@MaxEndorseIndex ,
@SopSSN ,
@ProcessBeginTime,
@ProcessEndTime,
@ProcessStatus ,
@Re )
IF (@@ERROR<>0)
ROLLBACK TRANSACTION Tran_BFS
ELSE
COMMIT TRANSACTION Tran_BFSreturn
GO
比如:UPDATE [tb] SET col = 'value' WHERE id = 10086如果id字段上有索引,更新语句支持找到id = 10086的数据,更新锁以及升级后的排它锁都是行级;
如果id字段上没有索引,更新语句需要扫描表来确定哪些记录需要更新,则更新锁会是表级,尽管排它锁是行级。
我想在insert a with (rowlock) 这样是不是可以把表级锁改为行锁啊?
只要修改数据就会有锁定。不是必然导致死锁。两个进程都在等待也未必是死锁,只有两个进程相互等待才是死锁。LZ检查一下BFS_ImageStoreInfo和BFS_BusinessInfo两个表上的索引。
的索引是BusinessId(BusinessId是业务报文的业务流水号。)BFS_ImageStoreInfo
的索引是BusinessGuid(BusinessGuid是对应BFS_BusinessInfo的系统内部编号,由程序自动生成。)
这两个索引没什么问题吧?
USE tempdb
GO/*
1,INSERT 的锁情况
*/IF OBJECT_ID('tb') IS NOT NULL DROP TABLE TBCREATE TABLE tb
(
id int,
col char(20)
)BEGIN TRAN IN_TB
INSERT INTO tb VALUES(1,'33')
--COMMIT TRAN IN_TB
/*
request_session_id resource_database_id resource_associated_entity_id resource_type resource_description request_mode request_status
------------------ -------------------- ----------------------------- ------------------------------------------------------------ ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------ ------------------------------------------------------------
55 2 1873497446010978304 RID 1:173:0 X GRANT
55 2 1873497446010978304 PAGE 1:173 IX GRANT
55 2 309576141 OBJECT IX GRANT
55 2 325576198 OBJECT IX GRANT
*//*
2,DELTE 的锁情况
*/BEGIN TRAN DE_TB
DELETE FROM tb WHERE ID=1
/*
request_session_id resource_database_id resource_associated_entity_id resource_type resource_description request_mode request_status
------------------ -------------------- ----------------------------- ------------------------------------------------------------ ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------ ------------------------------------------------------------
55 2 1801439851932090368 RID 1:173:0 X GRANT
55 2 1801439851932090368 PAGE 1:173 IX GRANT
55 2 309576141 OBJECT IX GRANT */因为考虑锁问题时,需要从多个方面来探讨
1、锁的粒度
2、锁的模式
3、隔离级别加索引后,在不同的隔离级别下有所不同。而且索引还分聚集索引与非聚集索引之分。
一般而言:
如果是非聚集索引,需要对leaf页加锁,有时候反而增加了负担;
如果是聚集索引,是对索引加锁,与对heap表加锁差别应该不是很大。
INSERT的表默认只加行级锁,上面有人已经说了。
BFS_ImageStoreInfo的索引是BusinessGuid
这两个都是非聚集索引吗?
if (@n>0)
begin
delete from BFS_ImageStoreInfo
where BusinessGuid=(
select BusinessGuid from BFS_BusinessInfo with (nolock)
where BusinessId= @BusinessId )
--1. BFS_ImageStoreInfo索引页BusinessGuid的更新锁
--2. BFS_ImageStoreInfo数据页的排它锁
delete from BFS_BusinessInfo
where BusinessId=@BusinessId
--3. BFS_BusinessInfo索引页BusinessId的更新锁
--4. BFS_BusinessInfo数据页的排它锁
endinsert into BFS_BusinessInfo
--5. BFS_BusinessInfo数据页的排它锁从这个存储过程分析,可能产生死锁的地方是第3步和第5步。
但这些应该都是行级锁。最好用Profiler跟踪一下,监控一下实际加锁过程。
-- 创建表索引
IF EXISTS (SELECT name FROM sys.indexes
WHERE name = N'IX_BFS_BusinessInfo')
DROP INDEX IX_BFS_BusinessInfo ON BFS_BusinessInfo ;
GO
CREATE INDEX IX_BFS_BusinessInfo
ON BFS_BusinessInfo (BusinessId);
GO
如果我在delete那里加一个事务,insert那里加一个事务,两个数据库事务,能不能解决问题呢?
怎么用?
怎么看profiler的日志?
http://www.sqlservercentral.com/articles/books/65797/或者用dbcc traceon(1222,-1)
dbcc traceon(1204,-1)
然后在errorlog里面也是可以看到的。
就是在delete的时候是一个事务,insert是一个事务。
这样可不可以解决死锁的问题,
还是在insert那里加一个with(rowlock)可不可以减少死锁的问题。
delete from BFS_ImageStoreInfo
where BusinessGuid=(
select BusinessGuid from BFS_BusinessInfo with (nolock)
where BusinessId= @BusinessId ) --删除已存在的业务信息
delete from BFS_BusinessInfo
where BusinessId=@BusinessId 这两个步骤,一次要删除多少数据?
delete from BFS_ImageStoreInfo
where BusinessGuid=(
select BusinessGuid from BFS_BusinessInfo with (nolock)
where BusinessId= @BusinessId )
删除2条--删除已存在的业务信息
delete from BFS_BusinessInfo
where BusinessId=@BusinessId
删除1条
--删除已存在的影像存储信息
delete from BFS_ImageStoreInfo
where BusinessGuid=(
select BusinessGuid from BFS_BusinessInfo with (nolock)
where BusinessId= @BusinessId ) --删除已存在的业务信息
delete from BFS_BusinessInfo
where BusinessId=@BusinessId 看看结果。
表 'BFS_BusinessInfo'。扫描计数 1,逻辑读取 2 次,物理读取 0 次,预读 0 次,lob 逻辑读取 0 次,lob 物理读取 0 次,lob 预读 0 次。(2 行受影响)(8 行受影响)
表 'BFS_BusinessInfo'。扫描计数 1,逻辑读取 8 次,物理读取 0 次,预读 0 次,lob 逻辑读取 4 次,lob 物理读取 0 次,lob 预读 0 次。(1 行受影响)(4 行受影响)这个是执行后的消息。
结果是
2,1,delete from BFS_ImageStoreInfo
where BusinessGuid=(
select BusinessGuid from BFS_BusinessInfo with (nolock)
where BusinessId= 'abc1234' ) --删除已存在的业务信息,1,1,0,NULL,NULL,NULL,NULL,1,NULL,NULL,NULL,0.02657376,NULL,NULL,DELETE,0,NULL
2,1, |--Clustered Index Delete(OBJECT:([BFSDB].[dbo].[BFS_ImageStoreInfo].[PK__BFS_ImageStoreIn__0AD2A005]), OBJECT:([BFSDB].[dbo].[BFS_ImageStoreInfo].[IX_BFS_ImageStoreInfo])),1,2,1,Clustered Index Delete,Delete,OBJECT:([BFSDB].[dbo].[BFS_ImageStoreInfo].[PK__BFS_ImageStoreIn__0AD2A005]), OBJECT:([BFSDB].[dbo].[BFS_ImageStoreInfo].[IX_BFS_ImageStoreInfo]),NULL,1,0.02,2E-06,9,0.02657376,NULL,NULL,PLAN_ROW,0,1
2,1, |--Top(ROWCOUNT est 0),1,3,2,Top,Top,TOP EXPRESSION:((0)),NULL,1,0,1E-07,17,0.00657176,[BFSDB].[dbo].[BFS_ImageStoreInfo].[ImageStoreGuid],NULL,PLAN_ROW,0,1
2,1, |--Nested Loops(Inner Join, OUTER REFERENCES:([Expr1011])),1,4,3,Nested Loops,Inner Join,OUTER REFERENCES:([Expr1011]),NULL,1,0,4.18E-06,17,0.00657166,[BFSDB].[dbo].[BFS_ImageStoreInfo].[ImageStoreGuid],NULL,PLAN_ROW,0,1
1,1, |--Assert(WHERE:(CASE WHEN [Expr1010]>(1) THEN (0) ELSE NULL END)),1,5,4,Assert,Assert,WHERE:(CASE WHEN [Expr1010]>(1) THEN (0) ELSE NULL END),NULL,1,0,1.8E-07,36,0.00328438,[Expr1011],NULL,PLAN_ROW,0,1
1,1, | |--Stream Aggregate(DEFINE:([Expr1010]=Count(*), [Expr1011]=ANY([BFSDB].[dbo].[BFS_BusinessInfo].[BusinessGuid]))),1,6,5,Stream Aggregate,Aggregate,NULL,[Expr1010]=Count(*), [Expr1011]=ANY([BFSDB].[dbo].[BFS_BusinessInfo].[BusinessGuid]),1,0,1.1E-06,44,0.0032842,[Expr1010], [Expr1011],NULL,PLAN_ROW,0,1
1,1, | |--Index Seek(OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[IX_BFS_BusinessInfo]), SEEK:([BFSDB].[dbo].[BFS_BusinessInfo].[BusinessId]='abc1234') ORDERED FORWARD),1,7,6,Index Seek,Index Seek,OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[IX_BFS_BusinessInfo]), SEEK:([BFSDB].[dbo].[BFS_BusinessInfo].[BusinessId]='abc1234') ORDERED FORWARD,[BFSDB].[dbo].[BFS_BusinessInfo].[BusinessGuid],1,0.003125,0.0001581,47,0.0032831,[BFSDB].[dbo].[BFS_BusinessInfo].[BusinessGuid],NULL,PLAN_ROW,0,1
2,1, |--Index Seek(OBJECT:([BFSDB].[dbo].[BFS_ImageStoreInfo].[IX_BFS_ImageStoreInfo]), SEEK:([BFSDB].[dbo].[BFS_ImageStoreInfo].[BusinessGuid]=[Expr1011]) ORDERED FORWARD),1,12,4,Index Seek,Index Seek,OBJECT:([BFSDB].[dbo].[BFS_ImageStoreInfo].[IX_BFS_ImageStoreInfo]), SEEK:([BFSDB].[dbo].[BFS_ImageStoreInfo].[BusinessGuid]=[Expr1011]) ORDERED FORWARD,[BFSDB].[dbo].[BFS_ImageStoreInfo].[ImageStoreGuid],1,0.003125,0.0001581,17,0.0032831,[BFSDB].[dbo].[BFS_ImageStoreInfo].[ImageStoreGuid],NULL,PLAN_ROW,0,11,1,DELETE [BFS_BusinessInfo] WHERE [BusinessId]=@1,2,1,0,NULL,NULL,NULL,NULL,1,NULL,NULL,NULL,0.0232852,NULL,NULL,DELETE,0,NULL
1,1, |--Clustered Index Delete(OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[PK__BFS_BusinessInfo__08EA5793]), OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[IX_BFS_BusinessInfo])),2,2,1,Clustered Index Delete,Delete,OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[PK__BFS_BusinessInfo__08EA5793]), OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[IX_BFS_BusinessInfo]),NULL,1,0.02,2E-06,9,0.0232852,NULL,NULL,PLAN_ROW,0,1
1,1, |--Top(ROWCOUNT est 0),2,3,2,Top,Top,TOP EXPRESSION:((0)),NULL,1,0,1E-07,47,0.0032832,[BFSDB].[dbo].[BFS_BusinessInfo].[BusinessGuid],NULL,PLAN_ROW,0,1
1,1, |--Index Seek(OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[IX_BFS_BusinessInfo]), SEEK:([BFSDB].[dbo].[BFS_BusinessInfo].[BusinessId]=[@1]) ORDERED FORWARD),2,4,3,Index Seek,Index Seek,OBJECT:([BFSDB].[dbo].[BFS_BusinessInfo].[IX_BFS_BusinessInfo]), SEEK:([BFSDB].[dbo].[BFS_BusinessInfo].[BusinessId]=[@1]) ORDERED FORWARD,[BFSDB].[dbo].[BFS_BusinessInfo].[BusinessGuid],1,0.003125,0.0001581,47,0.0032831,[BFSDB].[dbo].[BFS_BusinessInfo].[BusinessGuid],NULL,PLAN_ROW,0,1
这个有影响吗?
我看应用程序的日志,这两个操作的时间间隔很短。会不会有什么影响的。
USE BFSDB
IF EXISTS (SELECT * FROM sysobjects WHERE type = 'P' AND name = 'up_UpdateBFSBusinessStatus')
BEGIN
DROP Procedure up_UpdateBFSBusinessStatus
ENDGO/******************************************************************************
** File: up_UpdateBFSBusinessStatus.Sql
** Name: up_UpdateBFSBusinessStatus
** Desc: 更新业务状态
** Return Value:
**
** Auth:
** Date: 2008-04-23
*******************************************************************************
** Change History
*******************************************************************************
** Date: Author: Description:
** -------- -------- ---------------------------------------
**
*******************************************************************************/
CREATE Procedure up_UpdateBFSBusinessStatus
(
@BusinessId varchar(20) , -- 业务流水号
@ProcessEndTime datetime, --处理结束时间
@ProcessStatus int , -- 处理状态
@Re text -- 描述)AS
BEGIN TRANSACTION Tran_BFSupdate BFS_BusinessInfo
set
ProcessEndTime=@ProcessEndTime,
ProcessStatus=@ProcessStatus,
Re=@Re
where BusinessId=@BusinessId and ProcessStatus=0
IF (@@ERROR<>0)
ROLLBACK TRANSACTION Tran_BFS
ELSE
COMMIT TRANSACTION Tran_BFSGO
把
--删除已存在的业务信息
delete from BFS_BusinessInfo
where BusinessId=@BusinessId
作为一个单独的事务来处理。这样,我这个存储过程就有三个事务。
我刚刚问别人,
他们说是
delete from BFS_BusinessInfo
where BusinessId=@BusinessId
这里造成的死锁。
所以我把这个语句写成了一个事务。