Mysql数据库采用InnoDB模式，默认参数:innodb_lock_wait_timeout设置锁等待的时间是50s，一旦数据库锁超过这个时间就会报错。

mysql> SHOW GLOBAL VARIABLES LIKE 'innodb_lock_wait_timeout';

+--------------------------+-------+

| Variable_name | Value |

+--------------------------+-------+

| innodb_lock_wait_timeout | 50 |

+--------------------------+-------+

1 row in set (0.00 sec)

mysql> SET GLOBAL innodb_lock_wait_timeout=120;

Query OK, 0 rows affected (0.00 sec)

mysql> SHOW GLOBAL VARIABLES LIKE 'innodb_lock_wait_timeout';

+--------------------------+-------+

| Variable_name | Value |

+--------------------------+-------+

| innodb_lock_wait_timeout | 120 |

+--------------------------+-------+

1 row in set (0.00 sec)

mysql>