以下的文章主要是对MySQL数据库命令的基础的详细解析,我们首先是以显示MySQL数据库的基本信息开始的,来对MySQL数据库命令的基础进行一个详细的解析,以下就是文章的具体内容的描述。 显示MySQL基本信息: MySQL status; 查看变量: showvariableslike'%ver
以下的文章主要是对MySQL数据库命令的基础的详细解析,我们首先是以显示MySQL数据库的基本信息开始的,来对MySQL数据库命令的基础进行一个详细的解析,以下就是文章的具体内容的描述。
显示MySQL基本信息:
<ol class="dp-xml"><li class="alt"><span><span>MySQL</span><span class="tag">></span><span>status; </span></span></li></ol>
查看变量:
<ol class="dp-xml"><li class="alt"><span><span>show variables like '%version%'; </span></span></li></ol>
备份与还原MySQL数据库命令:在最后还有
1.备份MySQL数据库的命令:
在cmd中进入到MySQL的lib目录下执行如下:
<ol class="dp-xml"><li class="alt"><span><span>MySQLdump -hhostname -uusername -ppassword databaseName </span><span class="tag">></span><span> backupfile.sql </span></span></li></ol>
例:
MySQLdump -hlocalhost -uroot -p123456 test > test.sql
2.导出一个表:
MySQLdump -u 用户名 -p 数据库名 表名> 导出的文件名
<ol class="dp-xml"><li class="alt"><span><span>MySQLdump -u root -p dataname users</span><span class="tag">></span><span> dataname_users.sql </span></span></li></ol>
还原MySQL数据库的MySQL数据库命令:
首先新建一个数据库:create database 数据库;
然后进入数据库:use 数据库名;
然后执行sql脚本:MySQL>source d:\aaa.sql;
完成
帮助MySQL数据库命令:进入lib目录下MySQLdump -help
注:如果配置了环境变量就不用进入lib下就可以直接运行
连接MySQL
先执行MySQL安装目录下的MySQLd.exe启动服务
进入MySQL管理界面
MySQL -h localhost -u root -p
-h 主机名 -u用户名 -p 密码
修改密码。
格式:MySQLadmin -u用户名 -p旧密码 password 新密码
MySQLadmin -u root -password ab12
注:因为开始时root没有密码,所以-p旧密码一项就可以省略了。
再将root的密码改为123456。
显示所有数据库
<ol class="dp-xml"><li class="alt"><span><span>show databases; </span></span></li></ol>
建立一个新库
<ol class="dp-xml"> <li class="alt"><span><span>create database new; </span></span></li> <li><span>drop database if exists school; </span></li> </ol>
如果存在SCHOOL则删除
使用这个数据库
<ol class="dp-xml"><li class="alt"><span><span>use new; </span></span></li></ol>
MySQL数据库命令:建立新表
<ol class="dp-xml"> <li class="alt"><span><span>create table app_user( </span></span></li> <li><span>username varchar(20), </span></li> <li class="alt"><span>password varchar(255), </span></li> <li><span>primary key(username)); </span></li> </ol>
显示表结构
<ol class="dp-xml"><li class="alt"><span><span>describe app_user;/desc app_user; </span></span></li></ol>
显示所有表
<ol class="dp-xml"><li class="alt"><span><span>show tables; </span></span></li></ol>
插入测试数据
<ol class="dp-xml"> <li class="alt"><span><span>insert into app_user values('tomcat' , '123'); </span></span></li> <li><span>insert into app_user values('yeeku' , '123'); </span></li> </ol>
退出MySQL管理界面
<ol class="dp-xml"><li class="alt"><span><span>exit/quit; </span></span></li></ol>
以上的相关内容就是对MySQL数据库基础的介绍,望你能有所收获。

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