The locks are normally next-key locks that also block inserts into the “gap” immediately before the record.
mysql> select @@tx_isolation;
+-----------------+
| @@tx_isolation |
+-----------------+
| REPEATABLE-READ |
+-----------------+
1 row in set (0.00 sec)
第一种情况 更新列没有索引:
CREATE TABLE `SmsTest` (
`sn` int(11) NOT NULL AUTO_INCREMENT COMMENT '自增编号',
`phoneNo` int(16) NOT NULL,
`channelType` int(11) DEFAULT NULL COMMENT '通道识别',
`status` tinyint(4) NOT NULL COMMENT '短信转态,1.发送成功,2.发送失败,3.发送异常',
PRIMARY KEY (`sn`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='短信发送成功记录表';
mysql> show create table SmsTest\G;
*************************** 1. row ***************************
Table: SmsTest
Create Table: CREATE TABLE `SmsTest` (
`sn` int(11) NOT NULL AUTO_INCREMENT COMMENT '自增编号',
`phoneNo` int(16) NOT NULL,
`channelType` int(11) DEFAULT NULL COMMENT '通道识别',
`status` tinyint(4) NOT NULL COMMENT '短信转态,1.发送成功,2.发送失败,3.发送异常',
PRIMARY KEY (`sn`)
) ENGINE=InnoDB AUTO_INCREMENT=22 DEFAULT CHARSET=utf8 COMMENT='短信发送成功记录表'
1 row in set (0.00 sec)
ERROR:
No query specified
mysql> show index from SmsTest;
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| SmsTest | 0 | PRIMARY | 1 | sn | A | 16 | NULL | NULL | | BTREE | | |
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
1 row in set (0.00 sec)
mysql> select * from SmsTest;
+----+---------+-------------+--------+
| sn | phoneNo | channelType | status |
+----+---------+-------------+--------+
| 1 | 1 | 2 | 1 |
| 2 | 2 | 2 | 1 |
| 3 | 3 | 2 | 1 |
| 4 | 4 | 2 | 1 |
| 5 | 5 | 2 | 1 |
| 6 | 6 | 2 | 1 |
| 7 | 7 | 2 | 1 |
| 8 | 8 | 2 | 1 |
| 9 | 9 | 2 | 1 |
| 10 | 10 | 1 | 1 |
| 16 | 16 | 45 | 56 |
| 17 | 17 | 2 | 1 |
| 18 | 18 | 1 | 1 |
| 19 | 19 | 1 | 1 |
| 20 | 20 | 2 | 1 |
| 21 | 10 | 1 | 1 |
+----+---------+-------------+--------+
16 rows in set (0.00 sec)
/*********第一种情况 更新列没有索引:
Session 1:
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from SmsTest where phoneNo=16 for update;
+----+---------+-------------+--------+
| sn | phoneNo | channelType | status |
+----+---------+-------------+--------+
| 16 | 16 | 45 | 56 |
+----+---------+-------------+--------+
1 row in set (0.00 sec)
mysql[192.168.11.187] processid[3] root@localhost in db[zjzc] hold transaction time 55
You have new mail in /var/spool/mail/root
进程ID为3
Session 2:
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into SmsTest values(11,11,1,1); ##堵塞
2016-11-25 10:03:19,152,3,root,localhost,zjzc
mysql[192.168.11.187] processid[3] root@localhost in db[zjzc] hold transaction time 152
112072530,26,insert into SmsTest values(11,11,1,1),112072529,3,
mysql[192.168.11.187] blocking_thread[3] blocking_query[] blocking waiting_thread[26]'s insert into SmsTest values(11,11,1,1)
You have new mail in /var/spool/mail/root
mysql> insert into zjzc.SmsTest values(11,1,1,1);
mysql> insert into zjzc.SmsTest values(110,110,1,1); ###堵塞
mysql[192.168.11.187] blocking_thread[3] blocking_query[] blocking waiting_thread[34]'s insert into zjzc.SmsTest values(110,110,1,1)
mysql> insert into zjzc.SmsTest values(200,110,1,1);
112072532,34,insert into zjzc.SmsTest values(220,220,1,1),112072529,3,
mysql[192.168.11.187] blocking_thread[3] blocking_query[] blocking waiting_thread[34]'s insert into zjzc.SmsTest values(220,220,1,1)
Vsftp:/root# mysql -uroot -p1234567 -e"show processlist"
Warning: Using a password on the command line interface can be insecure.
+----+------+-----------+------+---------+------+--------+----------------------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+------+-----------+------+---------+------+--------+----------------------------------------------+
| 3 | root | localhost | zjzc | Sleep | 469 | | NULL |
| 34 | root | localhost | zjzc | Query | 7 | update | insert into zjzc.SmsTest values(220,220,1,1) |
| 41 | root | localhost | NULL | Query | 0 | init | show processlist |
+----+------+-----------+------+---------+------+--------+----------------------------------------------+
更新列没有索引,此时锁全表
/*********第一种情况 更新列有索引,但是非唯一索引
mysql> show create table zjzc.SmsTest\G;
*************************** 1. row ***************************
Table: SmsTest
Create Table: CREATE TABLE `SmsTest` (
`sn` int(11) NOT NULL AUTO_INCREMENT COMMENT '自增编号',
`phoneNo` int(16) NOT NULL,
`channelType` int(11) DEFAULT NULL COMMENT '通道识别',
`status` tinyint(4) NOT NULL COMMENT '短信转态,1.发送成功,2.发送失败,3.发送异常',
PRIMARY KEY (`sn`)
) ENGINE=InnoDB AUTO_INCREMENT=22 DEFAULT CHARSET=utf8 COMMENT='短信发送成功记录表'
1 row in set (0.00 sec)
ERROR:
No query specified
mysql> show index from SmsTest;
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| SmsTest | 0 | PRIMARY | 1 | sn | A | 15 | NULL | NULL | | BTREE | | |
+---------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
1 row in set (0.00 sec)
创建索引,在phoneNo 列上
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from SmsTest where phoneNo=16 for update;
+----+---------+-------------+--------+
| sn | phoneNo | channelType | status |
+----+---------+-------------+--------+
| 16 | 16 | 45 | 56 |
+----+---------+-------------+--------+
1 row in set (0.00 sec)
Session 2:
mysql> insert into SmsTest values(99,9,1,1);
Query OK, 1 row affected (0.00 sec)
mysql> insert into SmsTest values(99,10,1,1); ##堵塞
mysql> insert into SmsTest values(11,11,1,1); ##堵塞
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
mysql>
mysql[192.168.11.187] processid[1] root@localhost in db[zjzc] hold transaction time 40
112074074,25,insert into SmsTest values(11,11,1,1),112074073,1,
mysql[192.168.11.187] blocking_thread[1] blocking_query[] blocking waiting_thread[25]'s insert into SmsTest values(11,11,1,1)
mysql> insert into SmsTest values(12,12,1,1);
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
mysql> insert into SmsTest values(13,13,1,1);
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
mysql> insert into SmsTest values(14,14,1,1);
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
mysql> insert into SmsTest values(14,14,1,1);
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
mysql> insert into SmsTest values(15,15,1,1);
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
mysql> insert into SmsTest values(16,16,1,1);
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
mysql> insert into SmsTest values(17,17,1,1);
ERROR 1062 (23000): Duplicate entry '17' for key 'PRIMARY'
mysql> insert into SmsTest values(99,17,1,1);
ERROR 1062 (23000): Duplicate entry '99' for key 'PRIMARY'
mysql> insert into SmsTest values(999,17,1,1);
Query OK, 1 row affected (0.00 sec)
更新列上有唯一索引 ,锁住的区间为【10,16】
/*********第一种情况 更新列有索引,且是唯一索引
mysql> create unique index SmsTest_idx1 on SmsTest(phoneNo);
Query OK, 0 rows affected (0.02 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> show create table SmsTest\G;
*************************** 1. row ***************************
Table: SmsTest
Create Table: CREATE TABLE `SmsTest` (
`sn` int(11) NOT NULL AUTO_INCREMENT COMMENT '自增编号',
`phoneNo` int(16) NOT NULL,
`channelType` int(11) DEFAULT NULL COMMENT '通道识别',
`status` tinyint(4) NOT NULL COMMENT '短信转态,1.发送成功,2.发送失败,3.发送异常',
PRIMARY KEY (`sn`),
UNIQUE KEY `SmsTest_idx1` (`phoneNo`)
) ENGINE=InnoDB AUTO_INCREMENT=21 DEFAULT CHARSET=utf8 COMMENT='短信发送成功记录表'
1 row in set (0.00 sec)
ERROR:
No query specified
Session 1:
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from SmsTest where phoneNo=16 for update;
+----+---------+-------------+--------+
| sn | phoneNo | channelType | status |
+----+---------+-------------+--------+
| 16 | 16 | 45 | 56 |
+----+---------+-------------+--------+
1 row in set (0.00 sec)
Session 2:
mysql> use zjzc;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> insert into SmsTest values(11,11,1,1);
Query OK, 1 row affected (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into SmsTest values(12,12,1,1);
Query OK, 1 row affected (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into SmsTest values(13,13,1,1);
Query OK, 1 row affected (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into SmsTest values(14,14,1,1);
Query OK, 1 row affected (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into SmsTest values(15,15,1,1);
Query OK, 1 row affected (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into SmsTest values(16,16,1,1); ##堵塞
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
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