什么是数据库死锁
2
go
3![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
4
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[p_lockinfo]') and OBJECTPROPERTY(id, N'IsProcedure') = 1)
5
drop procedure [dbo].[p_lockinfo]
6
GO
7![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
8
/*--处理死锁
9![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
10
查看当前进程,或死锁进程,并能自动杀掉死进程
11![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
12
因为是针对死锁的,所以如果有死锁进程,只能查看死锁进程
13
当然,你可以通过参数控制,不管有没有死锁,都只查看死锁进程
14![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
15
感谢: caiyunxia,jiangopen 两位提供的参考信息
16![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
17
--邹建 2004.04(引用请保留此信息)--*/
18![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
19
/*--调用示例
20![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
21
exec p_lockinfo
22
--*/
23
create proc p_lockinfo
24
@kill_lock_spid bit=1, --是否杀掉死锁的进程,1 杀掉, 0 仅显示
25
@show_spid_if_nolock bit=1 --如果没有死锁的进程,是否显示正常进程信息,1 显示,0 不显示
26
as
27
set nocount on
28
declare @count int,@s nvarchar(1000),@i int
29
select id=identity(int,1,1),标志,
30
进程ID=spid,线程ID=kpid,块进程ID=blocked,数据库ID=dbid,
31
数据库名=db_name(dbid),用户ID=uid,用户名=loginame,累计CPU时间=cpu,
32
登陆时间=login_time,打开事务数=open_tran, 进程状态=status,
33
工作站名=hostname,应用程序名=program_name,工作站进程ID=hostprocess,
34
域名=nt_domain,网卡地址=net_address
35
into #t from(
36
select 标志='死锁的进程',
37
spid,kpid,a.blocked,dbid,uid,loginame,cpu,login_time,open_tran,
38
status,hostname,program_name,hostprocess,nt_domain,net_address,
39
s1=a.spid,s2=0
40
from master..sysprocesses a join (
41
select blocked from master..sysprocesses group by blocked
42
)b on a.spid=b.blocked where a.blocked=0
43
union all
44
select '|_牺牲品_>',
45
spid,kpid,blocked,dbid,uid,loginame,cpu,login_time,open_tran,
46
status,hostname,program_name,hostprocess,nt_domain,net_address,
47
s1=blocked,s2=1
48
from master..sysprocesses a where blocked<>0
49
)a order by s1,s2
50![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
51
select @count=@@rowcount,@i=1
52![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
53
if @count=0 and @show_spid_if_nolock=1
54
begin
55
insert #t
56
select 标志='正常的进程',
57
spid,kpid,blocked,dbid,db_name(dbid),uid,loginame,cpu,login_time,
58
open_tran,status,hostname,program_name,hostprocess,nt_domain,net_address
59
from master..sysprocesses
60
set @count=@@rowcount
61
end
62![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
63
if @count>0
64
begin
65
create table #t1(id int identity(1,1),a nvarchar(30),b Int,EventInfo nvarchar(255))
66
if @kill_lock_spid=1
67
begin
68
declare @spid varchar(10),@标志 varchar(10)
69
while @i<=@count
70
begin
71
select @spid=进程ID,@标志=标志 from #t where id=@i
72
insert #t1 exec('dbcc inputbuffer('+@spid+')')
73
if @@rowcount=0 insert #t1(a) values(null)
74
if @标志='死锁的进程' exec('kill '+@spid)
75
set @i=@i+1
76
end
77
end
78
else
79
while @i<=@count
80
begin
81
select @s='dbcc inputbuffer('+cast(进程ID as varchar)+')' from #t where id=@i
82
insert #t1 exec(@s)
83
if @@rowcount=0 insert #t1(a) values(null)
84
set @i=@i+1
85
end
86
select a.*,进程的SQL语句=b.EventInfo
87
from #t a join #t1 b on a.id=b.id
88
order by 进程ID
89
end
90
set nocount off
91
go
每个使用关系型数据库的程序都可能遇到数据死锁的情况。理解什么是死锁之前先要了解锁定的概念:如果需要“修改”一条数据,首先数据库管理系统会在上面加锁,以保证在同一时间只有一个事务能进行修改操作。锁定(Locking)发生在当一个事务获得对某一资源的“锁”时,这时,其他的事务就不能更改这个资源了,这种机制的存在是为了保证数据一致性。
多数情况下,可以认为如果一个资源被锁定,它总会在以后某个时间被释放。而死锁发生在当多个进程访问同一数据库时,其中每个进程拥有的锁都是其他进程所需的,由此造成每个进程都无法继续下去。简单的说,进程A等待进程B释放他的资源,B又等待A释放他的资源,这样就互相等待就形成死锁。
- 导致数据库死锁的原因
一般情况只发生锁超时,就是一个进程需要访问数据库表或者字段的时候,另外一个程序正在执行带锁的访问(比如修改数据),那么这个进程就会等待,当等了很久锁还没有解除的话就会锁超时,报告一个系统错误,拒绝执行相应的SQL操作。
发生死锁的情况比较少,比如一个进程需要访问两个资源(数据库表或者字段),当获取一个资源的时候进程就对它执行锁定,然后等待下一个资源空闲,这时候如果另外一个进程也需要两个资源,而已经获得并锁定了第二个资源,那么就会死锁,因为当前进程锁定第一个资源等待第二个资源,而另外一个进程锁定了第二个资源等待第一个资源,两个进程都永远得不到满足。
- 数据库死锁的解决方案
use master --必须在master数据库中创建
2
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
3
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
4
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
5
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
6
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
7
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
8
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
9
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
10
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
11
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
12
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
13
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
14
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
15
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
16
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
17
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockEnd.gif)
18
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
19
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
20
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
21
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
22
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockEnd.gif)
23
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
24
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
25
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
26
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
27
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
28
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
29
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
30
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
31
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
32
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
33
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
34
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
35
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
36
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
37
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
38
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
39
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
40
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
41
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
42
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
43
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
44
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
45
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
46
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
47
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
48
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
49
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
50
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
51
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
52
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
53
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
54
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
55
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
56
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
57
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
58
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
59
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
60
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
61
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
62
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
63
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
64
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
65
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
66
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
67
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
68
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
69
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
70
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
71
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
72
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
73
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
74
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
75
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
76
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
77
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
78
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
79
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
80
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
81
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
82
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
83
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
84
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
85
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
86
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
87
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
88
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
89
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
90
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
91
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)