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HomeDatabaseMysql TutorialLinux命令对数据库操作方法

比如我们要备份mysql中已经存在的名为linux的数据库,要用到命令mysqldump命令格式如下:[root@linuxidc root]# mysqldump -u ro

比如我们要备份mysql中已经存在的名为linux的数据库,要用到命令mysqldump
命令格式如下:
[root@linuxidc root]# mysqldump -u root -p linux > /root/linux.sql
Enter password:在这里输入数据库的密码

通过上面的命令,我们要明白两件事,首先备份数据库是要以数据库管理员的身份备份;其次:备份目的地是/root,备份的文件名是linux.sql。其实备份的位置和文件名,,根据自己的情况来定。文件名可以自己来取,路径也可以自己来安排;比如我想把linux的数据库备份到/home/beinan,数据库的文件名为linuxsir031130.sql,所以应该输入如下的命令。

[root@linuxidc root]#mysqldump -u root -p linux > /home/beinan/linuxsir031130.sql
Enter password:在这里输入数据库管理员root的数据库密码

如果数据量大会占用很大空间,这时可以利用gzip压缩数据,命令如下:

#mysqldump -u root -p tm | gzip > tm_050519.sql.gz

这样我们到/home/beinan目录下就能发现mysql中名为linux的数据库的备份文件linuxsir031130.sql
综上所述,我们学习时要学会变通。

恢复:
首先我们还是要操作上面几个过程,比如添加数据库管理员(如果您没有添加过mysql数据库管理员的话),创建数据库等。
比如我们要把在/home/beinan这个目录中的linuxsir031130.sql这个备份,导入名为linux的数据库中,应该如下操作;
[root@linuxidc root]#mysql -u root -p linux Enter password:在这里输入密码

如果机器好,数据库比较小,几分钟就好了。

如何导出数据库表的数据?(不同于备份哦)

#mysql

(#mysql>use linux;)#可有可无

#mysql>select * from linux.table-name into outfile “/home/table-name.txt”;

#/home/table-name.txt 可能会报错,如果这样去掉/home直接”table-name.txt”

默认保存在/var/lib/mysql/table-name.txt

对mysql数据库常用命令的一点补充;

几个常用的mysql相关的管理命令
mysql 命令:基本文本的,显示和使用的mysql数据库。前面已经简单的提过用法;比如登录等。
mysqladmin 命令,用来创建和维护mysql数据库的命令,前面已经简单的提过;
isamchk 是用来修复、检查和优化.ism后缀的数据库文件;
mysqldump 是用于备份数据库,前面已经简单的说明过;
myisamchk 用来修复.myi后缀的数据库文件;

比如我们要检查名为linux的数据库.myi数据库表是否存在问题,应该用下面的命令;

要把mysqld服务器停下来
[root@linuxidc root]# /opt/mysql/share/mysql.server stop

然后执行
[root@linuxidc root]# /opt/mysql/bin/myisamchk /opt/mysql/var/linux/*.MYI

上面的命令的意思就是检查所有的.myi文件,数据库的目录在/opt/mysql/var/linux/目录中

如果有问题,应该用-r参数来修复
[root@linuxidc root]# /opt/mysql/bin/myisamchk -r /opt/mysql/var/linux/*.MYI

7]mysqlshow 命令:显示用户选择的数据库和表
[root@linuxidc root]# /opt/mysql/bin/mysqlshow -uroot -p [数据库名]

比如我要查看名为linux的数据库;应该是:

[root@linuxidc root]# /opt/mysql/bin/mysqlshow -uroot -p linux

linux

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