前两天生产库上出现了一个不大不小的故障,关于MySQL的存储引擎问题。这个故障所涉及到的是MySQL4.1.20的版本MyISAM存储引擎,一张1千多万的表。故障现象:在做
前两天生产库上出现了一个不大不小的故障,关于MySQL 的存储引擎问题。
这个故障所涉及到的是MySQL 4.1.20的版本MyISAM存储引擎,一张1千多万的表。
故障现象:
在做简单的SELECT查询的时候没有问题,但是做连接查询或者其他复杂查询的时候就报错了:具体的错误代码由于时间的问题被遗忘了。在系统日志中记录的错误如下图:
从错误信息中可以猜到了大概:存储引擎出了问题。
进到相应的数据库目录下,服务器空间,香港服务器,查看一下数据文件大小,有4G大小,这就不奇怪了.
MySQL 4版本的数据库创建的表默认最大文件大小就是4G 也就是说那个表满了,无法在插入数据了。其实版本4是支持超过4G数据文件大小的,需要在创建表的时候加上这么一句话: MAX_ROWS=1000000000 AVG_ROW_LENGTH=15000 。
执行myisamchk -dvv 表名字显示属性信息:
然后更改表的最大文件大小
alter table table_name MAX_ROWS=1000000000 AVG_ROW_LENGTH=15000;
执行这个修改时间比较长,大约在几个小时。
检查修改结果:
其中:Datafile length 4095052564 =4G
Max datafile length 281474976710654 就远远超过G这个单位了。
MySQL 版本5默认已经支持 Max datafile length 281474976710654 就不用在创建表的时候添加MAX_ROWS=1000000000 AVG_ROW_LENGTH=15000 参数了。
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