- 浏览: 957195 次
- 性别:
- 来自: 江西上饶
文章分类
- 全部博客 (460)
- p.spring (56)
- p.maven (20)
- p.ant (17)
- p.jee (18)
- p.jse (33)
- p.ofbiz (31)
- p.软件工程 (8)
- p.struts2 (5)
- p.hibernate (5)
- linux (25)
- 设计模式 (2)
- p.javascript (11)
- 硬件 (1)
- p.jsp (2)
- p.windows批处理 (1)
- 操作系统问题 (5)
- 算法 (1)
- p.mysql (7)
- p.sql (5)
- p.c (1)
- google产品 (0)
- 内存 (1)
- p.struts (1)
- p.freemarker (7)
- p.css (4)
- p.log4j (10)
- p.html (3)
- 淘宝产品 (0)
- 其他 (3)
- 编译器 (0)
- svn (4)
- p.spring.security (11)
- 图形 (0)
- p.xml (1)
- p.ssh (0)
- p.jquery (4)
- p.jdbc (3)
- p.flex (0)
- p.c++ (0)
- p.c#Net (0)
- p.assembly (0)
- p.sqlserver (0)
- p.其他 (3)
- p.webwork (21)
- p.wap (12)
- p.cglib (1)
- p.jee服务器 (11)
- windows (2)
- p.iphone (1)
- p.java.分布式与集群 (2)
- p.ibatis (16)
- p.eclipse (5)
- 架构 (2)
- http协议 (5)
- 我的个人标准 (2)
- 多线程 (1)
- 奇怪问题 (5)
- p.jira (13)
- p.httpclient (1)
- 服务器.apache (11)
- 安全防范 (1)
- p.PODAM (1)
- p.junit (16)
- fop (2)
- 硬盘安装 (1)
- powerdesigner (0)
- 单元测试 (1)
- apache commons (4)
- tomcat+apache集群 (10)
- 各类诡辩 (1)
- 安卓 (8)
- qvod (1)
- java编程基础知识考试考点及答案 (0)
- 工作总结 (4)
- oracle (0)
- spring的util工具 (3)
- json (2)
- maven (3)
- jms (19)
- p.bat (3)
- hadoop (2)
- git (3)
- nginx (1)
- p.移动开发 (1)
- shiro (3)
- 游戏破解 (1)
- react-native (7)
- ios开发 (1)
- webmagic (6)
- socks5 (1)
最新评论
-
weituotian:
说的不好,没人看的
公司系统中的菜单功能和权限功能 -
石不易:
非常详细的注解~
绑定端口和IP,Listen 与VirtualHost指令 -
spring_springmvc:
spring mvc demo教程源代码下载,地址:http: ...
spring mvc -
liyixing1:
PandaDONG 写道谢谢你啊,我已经下下来了,只是还有很多 ...
jira war安装 -
liyixing1:
PandaDONG 写道谢谢你啊,我已经下下来了,只是还有很多 ...
jira war安装
java.lang.Exception:
### Error updating database. Cause: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### Cause: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
; SQL []; Lock wait timeout exceeded; try restarting transaction; nested exception is java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
select * from information_schema.innodb_trx 之后找到了一个一直没有提交的只读事务,
kill 到了对应的线程后ok 了。
==============================================
转载:http://blog.sina.com.cn/s/blog_6bb63c9e0100s7cb.html
MySQL 5.5 -- innodb_lock_wait 锁 等待
记得以前,当出现:ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction,
要解决是一件麻烦的事情 ;
特别是当一个SQL执行完了,但未COMMIT,后面的SQL想要执行就是被锁,超时结束;
DBA光从数据库无法着手找出源头是哪个SQL锁住了;
有时候看看show engine innodb status , 并结合 show full processlist; 能暂时解决问题;但一直不能精确定位;
在5.5中,information_schema 库中增加了三个关于锁的表(MEMORY引擎);
innodb_trx ## 当前运行的所有事务
innodb_locks ## 当前出现的锁
innodb_lock_waits ## 锁等待的对应关系
看到这个就非常激动 ; 这可是解决了一个大麻烦,先来看一下表结构
root@127.0.0.1 : information_schema 13:28:38> desc innodb_locks;
+-------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------------+------+-----+---------+-------+
| lock_id | varchar(81) | NO | | | |#锁ID
| lock_trx_id | varchar(18) | NO | | | |#拥有锁的事务ID
| lock_mode | varchar(32) | NO | | | |#锁模式
| lock_type | varchar(32) | NO | | | |#锁类型
| lock_table | varchar(1024) | NO | | | |#被锁的表
| lock_index | varchar(1024) | YES | | NULL | |#被锁的索引
| lock_space | bigint(21) unsigned | YES | | NULL | |#被锁的表空间号
| lock_page | bigint(21) unsigned | YES | | NULL | |#被锁的页号
| lock_rec | bigint(21) unsigned | YES | | NULL | |#被锁的记录号
| lock_data | varchar(8192) | YES | | NULL | |#被锁的数据
+-------------+---------------------+------+-----+---------+-------+
10 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:28:56> desc innodb_lock_waits;
+-------------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+-------------+------+-----+---------+-------+
| requesting_trx_id | varchar(18) | NO | | | |#请求锁的事务ID
| requested_lock_id | varchar(81) | NO | | | |#请求锁的锁ID
| blocking_trx_id | varchar(18) | NO | | | |#当前拥有锁的事务ID
| blocking_lock_id | varchar(81) | NO | | | |#当前拥有锁的锁ID
+-------------------+-------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:29:05> desc innodb_trx ;
+----------------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------------+---------------------+------+-----+---------------------+-------+
| trx_id | varchar(18) | NO | | | |#事务ID
| trx_state | varchar(13) | NO | | | |#事务状态:
| trx_started | datetime | NO | | 0000-00-00 00:00:00 | |#事务开始时间;
| trx_requested_lock_id | varchar(81) | YES | | NULL | |#innodb_locks.lock_id
| trx_wait_started | datetime | YES | | NULL | |#事务开始等待的时间
| trx_weight | bigint(21) unsigned | NO | | 0 | |#
| trx_mysql_thread_id | bigint(21) unsigned | NO | | 0 | |#事务线程ID
| trx_query | varchar(1024) | YES | | NULL | |#具体SQL语句
| trx_operation_state | varchar(64) | YES | | NULL | |#事务当前操作状态
| trx_tables_in_use | bigint(21) unsigned | NO | | 0 | |#事务中有多少个表被使用
| trx_tables_locked | bigint(21) unsigned | NO | | 0 | |#事务拥有多少个锁
| trx_lock_structs | bigint(21) unsigned | NO | | 0 | |#
| trx_lock_memory_bytes | bigint(21) unsigned | NO | | 0 | |#事务锁住的内存大小(B)
| trx_rows_locked | bigint(21) unsigned | NO | | 0 | |#事务锁住的行数
| trx_rows_modified | bigint(21) unsigned | NO | | 0 | |#事务更改的行数
| trx_concurrency_tickets | bigint(21) unsigned | NO | | 0 | |#事务并发票数
| trx_isolation_level | varchar(16) | NO | | | |#事务隔离级别
| trx_unique_checks | int(1) | NO | | 0 | |#是否唯一性检查
| trx_foreign_key_checks | int(1) | NO | | 0 | |#是否外键检查
| trx_last_foreign_key_error | varchar(256) | YES | | NULL | |#最后的外键错误
| trx_adaptive_hash_latched | int(1) | NO | | 0 | |#
| trx_adaptive_hash_timeout | bigint(21) unsigned | NO | | 0 | |#
+----------------------------+---------------------+------+-----+---------------------+-------+
22 rows in set (0.01 sec)
下面我们来动手看看数据吧:
##建立测试数据:
use test;
create table tx1
(id int primary key ,
c1 varchar(20),
c2 varchar(30))
engine=innodb default charset = utf8 ;
insert into tx1 values
(1,'aaaa','aaaaa2'),
(2,'bbbb','bbbbb2'),
(3,'cccc','ccccc2');
commit;
###产生事务;
### Session1
start transaction;
update tx1 set c1='heyf',c2='heyf' where id =3 ;
## 产生事务,在innodb_trx就有数据 ;
root@127.0.0.1 : information_schema 13:38:21> select * from innodb_trx G
*************************** 1. row ***************************
trx_id: 3669D82
trx_state: RUNNING
trx_started: 2010-12-24 13:38:06
trx_requested_lock_id: NULL
trx_wait_started: NULL
trx_weight: 3
trx_mysql_thread_id: 2344
trx_query: NULL
trx_operation_state: NULL
trx_tables_in_use: 0
trx_tables_locked: 0
trx_lock_structs: 2
trx_lock_memory_bytes: 376
trx_rows_locked: 1
trx_rows_modified: 1
trx_concurrency_tickets: 0
trx_isolation_level: REPEATABLE READ
trx_unique_checks: 1
trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
trx_adaptive_hash_latched: 0
trx_adaptive_hash_timeout: 10000
1 row in set (0.00 sec)
### 由于没有产生锁等待,下面两个表没有数据 ;
root@127.0.0.1 : information_schema 13:38:31> select * from innodb_lock_waits G
Empty set (0.00 sec)
root@127.0.0.1 : information_schema 13:38:57> select * from innodb_locks G
Empty set (0.00 sec)
#### 产生锁等待
#### session 2
start transaction;
update tx1 set c1='heyfffff',c2='heyffffff' where id =3 ;
root@127.0.0.1 : information_schema 13:39:01> select * from innodb_trx G
*************************** 1. row ***************************
trx_id: 3669D83 ##第2个事务
trx_state: LOCK WAIT ## 处于等待状态
trx_started: 2010-12-24 13:40:07
trx_requested_lock_id: 3669D83:49:3:4 ##请求的锁ID
trx_wait_started: 2010-12-24 13:40:07
trx_weight: 2
trx_mysql_thread_id: 2346 ##线程 ID
trx_query: update tx1 set c1='heyfffff',c2='heyffffff' where id =3
trx_operation_state: starting index read
trx_tables_in_use: 1 ##需要用到1个表
trx_tables_locked: 1 ##有1个表被锁
trx_lock_structs: 2
trx_lock_memory_bytes: 376
trx_rows_locked: 1
trx_rows_modified: 0
trx_concurrency_tickets: 0
trx_isolation_level: REPEATABLE READ
trx_unique_checks: 1
trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
trx_adaptive_hash_latched: 0
trx_adaptive_hash_timeout: 10000
*************************** 2. row ***************************
trx_id: 3669D82 ##第1个事务
trx_state: RUNNING
trx_started: 2010-12-24 13:38:06
trx_requested_lock_id: NULL
trx_wait_started: NULL
trx_weight: 3
trx_mysql_thread_id: 2344
trx_query: NULL
trx_operation_state: NULL
trx_tables_in_use: 0
trx_tables_locked: 0
trx_lock_structs: 2
trx_lock_memory_bytes: 376
trx_rows_locked: 1
trx_rows_modified: 1
trx_concurrency_tickets: 0
trx_isolation_level: REPEATABLE READ
trx_unique_checks: 1
trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
trx_adaptive_hash_latched: 0
trx_adaptive_hash_timeout: 10000
2 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:40:12> select * from innodb_locks G
*************************** 1. row ***************************
lock_id: 3669D83:49:3:4 ## 第2个事务需要的锁
lock_trx_id: 3669D83
lock_mode: X
lock_type: RECORD
lock_table: `test`.`tx1`
lock_index: `PRIMARY`
lock_space: 49
lock_page: 3
lock_rec: 4
lock_data: 3
*************************** 2. row ***************************
lock_id: 3669D82:49:3:4 ## 第1个事务需要的锁
lock_trx_id: 3669D82
lock_mode: X
lock_type: RECORD
lock_table: `test`.`tx1`
lock_index: `PRIMARY`
lock_space: 49
lock_page: 3
lock_rec: 4
lock_data: 3
2 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:40:15> select * from innodb_lock_waits G
*************************** 1. row ***************************
requesting_trx_id: 3669D83 ## 请求锁的事务
requested_lock_id: 3669D83:49:3:4 ## 请求锁的锁ID
blocking_trx_id: 3669D82 ## 拥有锁的事务
blocking_lock_id: 3669D82:49:3:4 ## 拥有锁的锁ID
1 row in set (0.00 sec)
转载自http://www.23gou.cn/blog/articles/2015/11/02/1446442993634.html
### Error updating database. Cause: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### Cause: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
; SQL []; Lock wait timeout exceeded; try restarting transaction; nested exception is java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
select * from information_schema.innodb_trx 之后找到了一个一直没有提交的只读事务,
kill 到了对应的线程后ok 了。
==============================================
转载:http://blog.sina.com.cn/s/blog_6bb63c9e0100s7cb.html
MySQL 5.5 -- innodb_lock_wait 锁 等待
记得以前,当出现:ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction,
要解决是一件麻烦的事情 ;
特别是当一个SQL执行完了,但未COMMIT,后面的SQL想要执行就是被锁,超时结束;
DBA光从数据库无法着手找出源头是哪个SQL锁住了;
有时候看看show engine innodb status , 并结合 show full processlist; 能暂时解决问题;但一直不能精确定位;
在5.5中,information_schema 库中增加了三个关于锁的表(MEMORY引擎);
innodb_trx ## 当前运行的所有事务
innodb_locks ## 当前出现的锁
innodb_lock_waits ## 锁等待的对应关系
看到这个就非常激动 ; 这可是解决了一个大麻烦,先来看一下表结构
root@127.0.0.1 : information_schema 13:28:38> desc innodb_locks;
+-------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------+---------------------+------+-----+---------+-------+
| lock_id | varchar(81) | NO | | | |#锁ID
| lock_trx_id | varchar(18) | NO | | | |#拥有锁的事务ID
| lock_mode | varchar(32) | NO | | | |#锁模式
| lock_type | varchar(32) | NO | | | |#锁类型
| lock_table | varchar(1024) | NO | | | |#被锁的表
| lock_index | varchar(1024) | YES | | NULL | |#被锁的索引
| lock_space | bigint(21) unsigned | YES | | NULL | |#被锁的表空间号
| lock_page | bigint(21) unsigned | YES | | NULL | |#被锁的页号
| lock_rec | bigint(21) unsigned | YES | | NULL | |#被锁的记录号
| lock_data | varchar(8192) | YES | | NULL | |#被锁的数据
+-------------+---------------------+------+-----+---------+-------+
10 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:28:56> desc innodb_lock_waits;
+-------------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+-------------+------+-----+---------+-------+
| requesting_trx_id | varchar(18) | NO | | | |#请求锁的事务ID
| requested_lock_id | varchar(81) | NO | | | |#请求锁的锁ID
| blocking_trx_id | varchar(18) | NO | | | |#当前拥有锁的事务ID
| blocking_lock_id | varchar(81) | NO | | | |#当前拥有锁的锁ID
+-------------------+-------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:29:05> desc innodb_trx ;
+----------------------------+---------------------+------+-----+---------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------------+---------------------+------+-----+---------------------+-------+
| trx_id | varchar(18) | NO | | | |#事务ID
| trx_state | varchar(13) | NO | | | |#事务状态:
| trx_started | datetime | NO | | 0000-00-00 00:00:00 | |#事务开始时间;
| trx_requested_lock_id | varchar(81) | YES | | NULL | |#innodb_locks.lock_id
| trx_wait_started | datetime | YES | | NULL | |#事务开始等待的时间
| trx_weight | bigint(21) unsigned | NO | | 0 | |#
| trx_mysql_thread_id | bigint(21) unsigned | NO | | 0 | |#事务线程ID
| trx_query | varchar(1024) | YES | | NULL | |#具体SQL语句
| trx_operation_state | varchar(64) | YES | | NULL | |#事务当前操作状态
| trx_tables_in_use | bigint(21) unsigned | NO | | 0 | |#事务中有多少个表被使用
| trx_tables_locked | bigint(21) unsigned | NO | | 0 | |#事务拥有多少个锁
| trx_lock_structs | bigint(21) unsigned | NO | | 0 | |#
| trx_lock_memory_bytes | bigint(21) unsigned | NO | | 0 | |#事务锁住的内存大小(B)
| trx_rows_locked | bigint(21) unsigned | NO | | 0 | |#事务锁住的行数
| trx_rows_modified | bigint(21) unsigned | NO | | 0 | |#事务更改的行数
| trx_concurrency_tickets | bigint(21) unsigned | NO | | 0 | |#事务并发票数
| trx_isolation_level | varchar(16) | NO | | | |#事务隔离级别
| trx_unique_checks | int(1) | NO | | 0 | |#是否唯一性检查
| trx_foreign_key_checks | int(1) | NO | | 0 | |#是否外键检查
| trx_last_foreign_key_error | varchar(256) | YES | | NULL | |#最后的外键错误
| trx_adaptive_hash_latched | int(1) | NO | | 0 | |#
| trx_adaptive_hash_timeout | bigint(21) unsigned | NO | | 0 | |#
+----------------------------+---------------------+------+-----+---------------------+-------+
22 rows in set (0.01 sec)
下面我们来动手看看数据吧:
##建立测试数据:
use test;
create table tx1
(id int primary key ,
c1 varchar(20),
c2 varchar(30))
engine=innodb default charset = utf8 ;
insert into tx1 values
(1,'aaaa','aaaaa2'),
(2,'bbbb','bbbbb2'),
(3,'cccc','ccccc2');
commit;
###产生事务;
### Session1
start transaction;
update tx1 set c1='heyf',c2='heyf' where id =3 ;
## 产生事务,在innodb_trx就有数据 ;
root@127.0.0.1 : information_schema 13:38:21> select * from innodb_trx G
*************************** 1. row ***************************
trx_id: 3669D82
trx_state: RUNNING
trx_started: 2010-12-24 13:38:06
trx_requested_lock_id: NULL
trx_wait_started: NULL
trx_weight: 3
trx_mysql_thread_id: 2344
trx_query: NULL
trx_operation_state: NULL
trx_tables_in_use: 0
trx_tables_locked: 0
trx_lock_structs: 2
trx_lock_memory_bytes: 376
trx_rows_locked: 1
trx_rows_modified: 1
trx_concurrency_tickets: 0
trx_isolation_level: REPEATABLE READ
trx_unique_checks: 1
trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
trx_adaptive_hash_latched: 0
trx_adaptive_hash_timeout: 10000
1 row in set (0.00 sec)
### 由于没有产生锁等待,下面两个表没有数据 ;
root@127.0.0.1 : information_schema 13:38:31> select * from innodb_lock_waits G
Empty set (0.00 sec)
root@127.0.0.1 : information_schema 13:38:57> select * from innodb_locks G
Empty set (0.00 sec)
#### 产生锁等待
#### session 2
start transaction;
update tx1 set c1='heyfffff',c2='heyffffff' where id =3 ;
root@127.0.0.1 : information_schema 13:39:01> select * from innodb_trx G
*************************** 1. row ***************************
trx_id: 3669D83 ##第2个事务
trx_state: LOCK WAIT ## 处于等待状态
trx_started: 2010-12-24 13:40:07
trx_requested_lock_id: 3669D83:49:3:4 ##请求的锁ID
trx_wait_started: 2010-12-24 13:40:07
trx_weight: 2
trx_mysql_thread_id: 2346 ##线程 ID
trx_query: update tx1 set c1='heyfffff',c2='heyffffff' where id =3
trx_operation_state: starting index read
trx_tables_in_use: 1 ##需要用到1个表
trx_tables_locked: 1 ##有1个表被锁
trx_lock_structs: 2
trx_lock_memory_bytes: 376
trx_rows_locked: 1
trx_rows_modified: 0
trx_concurrency_tickets: 0
trx_isolation_level: REPEATABLE READ
trx_unique_checks: 1
trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
trx_adaptive_hash_latched: 0
trx_adaptive_hash_timeout: 10000
*************************** 2. row ***************************
trx_id: 3669D82 ##第1个事务
trx_state: RUNNING
trx_started: 2010-12-24 13:38:06
trx_requested_lock_id: NULL
trx_wait_started: NULL
trx_weight: 3
trx_mysql_thread_id: 2344
trx_query: NULL
trx_operation_state: NULL
trx_tables_in_use: 0
trx_tables_locked: 0
trx_lock_structs: 2
trx_lock_memory_bytes: 376
trx_rows_locked: 1
trx_rows_modified: 1
trx_concurrency_tickets: 0
trx_isolation_level: REPEATABLE READ
trx_unique_checks: 1
trx_foreign_key_checks: 1
trx_last_foreign_key_error: NULL
trx_adaptive_hash_latched: 0
trx_adaptive_hash_timeout: 10000
2 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:40:12> select * from innodb_locks G
*************************** 1. row ***************************
lock_id: 3669D83:49:3:4 ## 第2个事务需要的锁
lock_trx_id: 3669D83
lock_mode: X
lock_type: RECORD
lock_table: `test`.`tx1`
lock_index: `PRIMARY`
lock_space: 49
lock_page: 3
lock_rec: 4
lock_data: 3
*************************** 2. row ***************************
lock_id: 3669D82:49:3:4 ## 第1个事务需要的锁
lock_trx_id: 3669D82
lock_mode: X
lock_type: RECORD
lock_table: `test`.`tx1`
lock_index: `PRIMARY`
lock_space: 49
lock_page: 3
lock_rec: 4
lock_data: 3
2 rows in set (0.00 sec)
root@127.0.0.1 : information_schema 13:40:15> select * from innodb_lock_waits G
*************************** 1. row ***************************
requesting_trx_id: 3669D83 ## 请求锁的事务
requested_lock_id: 3669D83:49:3:4 ## 请求锁的锁ID
blocking_trx_id: 3669D82 ## 拥有锁的事务
blocking_lock_id: 3669D82:49:3:4 ## 拥有锁的锁ID
1 row in set (0.00 sec)
转载自http://www.23gou.cn/blog/articles/2015/11/02/1446442993634.html
发表评论
-
mysql 保存表情符号 incorrect string value
2017-11-13 21:29 15791. mysql结构字段或者表,设置字段为 字符编码:utf ... -
linux安装mysql
2014-12-07 18:41 844http://blog.csdn.net/superchano ... -
mysql忘记root密码
2014-12-04 11:58 829http://jingyan.baidu.com/articl ... -
MySQL 错误1418 的原因分析及解决方法
2014-12-01 15:24 829具体错误: 使用mysql创建、调用存储过程,函数以及触 ... -
时间重叠的判断
2014-02-14 11:16 1645如上图,粗线是时间1 细线是时间2 时间重叠,只可能是以上四 ... -
使用MySQL的LAST_INSERT_ID
2011-10-10 00:04 1076LAST_INSERT_ID 自动返回最后一个 INSERT ...
相关推荐
在MySQL数据库操作中,"SQLSTATE[HY000]: General error: 1205 Lock wait timeout exceeded" 是一个常见的错误,它意味着在执行事务时,系统等待锁定资源的时间超过了预设的限制。这个错误通常发生在并发环境中,当...
- **innodb_lock_wait_timeout**:设置在等待锁时的超时时间,单位为秒。如果超过了这个时间还没有获取到锁,那么会抛出错误并提示用户重启事务。 ##### 3. 锁相关字典表查询和命令 MySQL提供了几个系统视图来查看...
python pymysql 无法登陆,报错pymysql.err.InternalError: (1698, "Access denied for user 'root'@'localhost'")或pymysql.err.InternalError: (1045, "Access denied for user 'root'@'localhost'"),详细报错...
5. Lock wait timeout exceeded 当事务中的操作无法立即获得锁定时,会等待一段时间,超时后抛出错误。这可能是死锁的信号,应检查事务的执行顺序,避免循环等待。 6. InnoDB与MyISAM的区别 InnoDB支持事务和行级...
ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement mysql> flush privileges; Query OK, 0 rows affected (0.00 sec) mysql> mysql
如果Session 1长时间未提交,Session 2会收到`Lock wait timeout exceeded`错误。可以通过`innodb_lock_wait_timeout`配置参数调整超时时间。 **乐观锁(Optimistic Lock)** 乐观锁则相反,它在读取数据时不加锁...
在SQL Server 2008中,死锁是指两个或多个并发事务互相等待对方释放资源,从而导致它们都无法继续执行的情况。当出现死锁时,SQL Server会选择一个会话作为"死锁牺牲品",结束该会话的事务并回滚其操作,以此来打破...
在实际操作中,为了防止因事务隔离级别导致的问题,如"Lock wait timeout exceeded"错误,可能需要将MySQL的事务级别设置为`READ COMMITTED`。 一旦主服务器配置完成,就可以在备用服务器上重复类似步骤,但要使用...
`Error: ER_LOCK_WAIT_TIMEOUT: Lock wait timeout exceeded; try restarting transaction`表明某个事务在等待其他事务释放锁资源时超过了预设的超时时间。事务是数据库操作的重要组成部分,它确保了数据的一致性和...
3. **合理设置锁等待超时**:通过调整`innodb_lock_wait_timeout`系统变量,可以控制事务等待锁的最大时间,避免长时间阻塞其他事务。 4. **使用乐观锁**:在读多写少的场景下,考虑使用乐观锁策略,减少锁定冲突。 ...
此外,两种环境都存在等待问题,导致Lock wait timeout exceeded错误。 **3. 自定义SQL测试** 针对特定用户场景,进行了复杂查询SQL的自定义测试。在200个线程的高并发下,Mycat的CPU占用率为400%,而9个MySQL...
12. **Lock wait timeout exceeded try restarting transaction**:在MySQL中,如果事务等待锁的时间超过设定的超时时间,会出现此错误。分析事务逻辑,优化事务粒度,或者提高锁等待超时时间(innodb_lock_wait_...
- 分析常见错误代码及含义,例如:Table lock wait timeout exceeded;Too many connections等。 **2. 查询日志** - **定义与作用**:查询日志记录了客户端执行的所有SQL语句。主要用于审计、故障排查以及性能...