Question

我正在使用mysql 5.0.92。最近，我们对一个表有很多插入死锁，相对快速地插入（并更新或删除）行。我在StackOverflow，mysql文档和论坛中研究了这些问题，但没有理解这个问题。困扰我的一件事是，其中一个表根据innodb状态没有锁定任何资源。

以下是SHOW INNODB STATUS的输出：

*** (1) TRANSACTION:
TRANSACTION 0 2326105503, ACTIVE 0 sec, process no 18871, OS thread id 1078532416 inserting
mysql tables in use 1, locked 1
LOCK WAIT 3 lock struct(s), heap size 1216, undo log entries 1
MySQL thread id 225129, query id 126720476 192.168.999.999 the-user update
insert into the_table (creation_date, expiration_date, iid, ma_c, ma_cid, ma_ed, ma_lat, ma_long, ma_ln, ma_sd, ma_sid, uid, id) values ('2011-08-30 16:54:18.0', '2011-09-01 23:59:59.0', 1001, '', 'US', '2011-09-01 23:59:59.0', 33.72, -92.61, 'CITY_CENTER', '2011-08-31 23:59:59.0', '', 1010, 'xxx')
*** (1) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 15002 page no 5749 n bits 376 index `idx_iu` of table `the_db/the_table` trx id 0 2326105503 lock_mode X insert intention waiting
Record lock, heap no 1 PHYSICAL RECORD: n_fields 1; compact format; info bits 0
 0: len 8; hex 73757072656d756d; asc supremum;;

*** (2) TRANSACTION:
TRANSACTION 0 2326105502, ACTIVE 0 sec, process no 18871, OS thread id 1243085120 inserting, thread declared inside InnoDB 500
mysql tables in use 1, locked 1
4 lock struct(s), heap size 1216, undo log entries 2
MySQL thread id 223875, query id 126720499 192.168.999.999 the-user update
insert into the_table (creation_date, expiration_date, iid, ma_c, ma_cid,ma_ed, ma_lat, ma_long, ma_ln,ma_sd, ma_sid, uid, id) values ('2011-08-30 16:54:18.0','2011-12-14 23:59:59.0', 2002, 'Amsterdam', 'NL', '2011-10-04 16:45:00.0', 52.37, 4.89, 'CITY_CENTER', '2011-09-06 23:59:59.0', '', 2020, 'yyy')
*** (2) HOLDS THE LOCK(S):
RECORD LOCKS space id 15002 page no 5749 n bits 376 index `idx_iu` of table `the_db/the_table` trx id 0 2326105502 lock_mode X
Record lock, heap no 1 PHYSICAL RECORD: n_fields 1; compact format; info bits 0
 0: len 8; hex 73757072656d756d; asc supremum;;

Record lock, heap no 283 PHYSICAL RECORD: n_fields 3; compact format; info bits 32
 0: len 8; hex 80000000008b22f0; asc       " ;; 1: len 4; hex 8004ab2a; asc    *;; 2: len 30; hex 313331343732333235383338393330353936323430363039352020202020; asc 1314723258389305962406095     ;;

*** (2) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 15002 page no 5749 n bits 376 index `idx_iu` of table `the_db/the_table` trx id 0 2326105502 lock_mode X insert intention waiting
Record lock, heap no 1 PHYSICAL RECORD: n_fields 1; compact format; info bits 0
 0: len 8; hex 73757072656d756d; asc supremum;;

*** WE ROLL BACK TRANSACTION (1)

该表定义如下：

CREATE TABLE `the_table` (
  `id` char(30) NOT NULL default '',
  `iid` bigint(20) NOT NULL,
  `uid` int(11) NOT NULL,
  `creation_date` datetime default NULL,
  `expiration_date` datetime default NULL,
  `ma_sd` datetime default NULL,
  `ma_ed` datetime default NULL,
  `ma_c` varchar(255) default NULL,
  `ma_sid` varchar(3) default NULL,
  `ma_cid` varchar(3) default NULL,
  `ma_long` double default NULL,
  `ma_lat` double default NULL,
  `ma_ln` varchar(50) default NULL,
  PRIMARY KEY  (`id`),
  KEY `idx_iu` (`iid`,`uid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8

非常感谢帮助。

Answer 1

通常在使用相同表时有不同的事务时会发生死锁，但是当表以不同的顺序更改时。

E.g。如果事务1更新表1然后更新表2，并且如果有另一个事务首先更新表2然后再更新表1，那么如果这些事务频繁运行，则可能会出现死锁。

Mysql中插入的死锁

1 个答案: