mysql 表压缩
mysql中经常出现历史表,这些表不会进行修改数据的操作,只有读操作。那么我们可以对其进行压缩处理,缩减磁盘空间。Innodb表和MyISAM表的压缩指令不一样。下面分别来讨论:
一、InnoDB表
参考文章:http://blog.csdn.net/linghaowoneng/article/details/51491800。
简而言之就一下几点:
1、确保开启参数innodb_file_per_table=1;以及设置
innodb_file_format
=Barracuda。
2、更改表属性:
alter table table_name ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8;
3、压缩前后对比图
aaarticlea/png;base64,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" alt="" />压缩前
压缩后
查询效率基本没有变化。这里没有保存前后的图片
二、MyISAM表压缩
MyISAM的压缩用到的是myisampack指令。
数据文件大小为336M,索引大小为137M。开始压缩
能够发现数据文件和索引文件都表小了。
压缩后需要检查表
注意:压缩表之后InnoDB仍可以进行插入操作,但是有一定风险;MyISAM不可以插入,会报错。所以建议压缩有都不进行插入操作
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故事背景:用VMware搭建了几个操作系统相同的虚拟机.安装成功一台后,直接拷贝已经生成的VMDK文件来构建其它的虚拟机. 一般情况下,如果复制的各个虚拟机只是单独使用,并且这些虚拟机不加入到域(Ac ...
- mycat 新增分片和字符集
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- java--构造器与static
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- 深入理解Java虚拟机—JVM内存结构
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- Java中Exception的种类
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- Codeforces #528 Div2 F (1087F) Rock-Paper-Scissors Champion 树状数组+set
题意:n个人站成一排,初始时刻每个人手中都有一个图案,可能是石头,剪刀,布3个中的1种,之后会随机选取相邻的两个人玩石头剪刀布的游戏,输的人会离开(如果两个人图案相同,则随机选择一个人离开).执行(n ...
- 电脑安装unity3d有C盘逐渐爆满问题解决方案
打开unity3d软件,Edit - Preference - GI Cache选中 Custom Cache Location,切换到别的盘,然后点击 Clean Cache清空一次,再查看C盘,存 ...
- tee 可以看见输出并将其写入到一个文件中
如下使用tee命令在屏幕上看见输出并同样写入到日志文件my.log中: [root@localhost home]# top |tee my.log tee可以保证你同时在屏幕上看到top的 ...
- VMware内部错误解决办法
虚拟机内部错误,不要担心不是致命错误,往往是由于你的配置被禁用了或者VMware运行权限不够导致 检查你的VMware虚拟网卡是否被禁用 检查你的VMware的运行权限,直接管理员运行就够够的了
- Python沙盒环境配置
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