我今天遇到了同样的问题,每次触发都会导致堆栈溢出.原来我的Zend社区服务器安装附带了一个默认的my.cnf文件,其中thread_stack大小设置为128K,这导致每个线程中可用于堆栈的131072字节：

mysql> show variables where `Variable_name` = 'thread_stack';

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

| Variable_name | Value |

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

| thread_stack | 131072 |

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

所以我在/usr/local/zend/mysql/data/my.cnf中注释了这一行,重新启动了mysql守护进程,瞧！ default 192K是

mysql> show variables where `Variable_name` = 'thread_stack';

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

| Variable_name | Value |

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

| thread_stack | 196608 |

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

现在你的桌子& tchester的触发器工作完美:)(尽管请注意分隔符)

mysql> CREATE TABLE `job_title` (

-> `job_id` int(11) NOT NULL AUTO_INCREMENT,

-> `position_id` int(11) DEFAULT NULL,

-> `title` varchar(255) COLLATE latin1_general_cs NOT NULL,

-> `selectable` tinyint(4) NOT NULL DEFAULT '0',

-> PRIMARY KEY (`job_id`),

-> UNIQUE KEY `title` (`title`)

-> ) ENGINE=InnoDB;

Query OK, 0 rows affected (0.14 sec)

mysql> DELIMITER &&

mysql> create trigger job_position_trigger

-> before insert on job_title for each row

-> begin

-> if new.position_id is null then

-> set @position = (select max(position_id)+1 from job_title);

-> if @position is null then set @position = 1; end if;

-> set new.position_id = @position;

-> end if;

-> end;

-> &&

Query OK, 0 rows affected (0.29 sec)

mysql> DELIMITER ;

mysql> insert into job_title (title, selectable) values ("test", 1);

Query OK, 1 row affected (0.00 sec)

mysql> insert into job_title (title, selectable) values ("test2", 3);

Query OK, 1 row affected (0.00 sec)

mysql> select * from job_title;

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

| job_id | position_id | title | selectable |

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

| 1 | 1 | test | 1 |

| 2 | 2 | test2 | 3 |

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

2 rows in set (0.00 sec)

你得到的错误,131072字节堆栈使用的9024字节和所需的128000字节是有意义的：9024 128000> 131072.