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关于数据库:
mysql实战练习:
Home Database Mysql Tutorial mysql基础----)基本命令与13道练习_MySQL

mysql基础----)基本命令与13道练习_MySQL

May 27, 2016 pm 01:45 PM
Order Base

关于数据库:

数据库是软件开发人员要掌握的基本工具,软件的运行的过程就是操作数据的过程,数据库中的数据无非就是几个操作:增-删-查-改。 Mysql安装完成后,需要配置变量环境,找到配置路径path,然后把mysql安装目录bin文件导入就可以了。 然后运行cmd进入dos。
进入dos后输入:mysql -uroot -p密码

mysql实战练习:

然后就可以进入mysql的操作环境了。如下图:登录后我执行了一条: show databases命令,查看所有的库。 \

创建一个表,然后查看表的数据结构: \

删除一个字段: \

添加一个字段: \

添加两条数据: \

数据修改成功: \

数据修改失败了,但是无错误,后来发现了判断是否为空要执行的是 is null而不是=null
\
改为is null后修改成功: \

修改字段成功: \

我添加了多条数据,表格完成了: \

查询id=1的表格: \

通过别名输入id=1的表格数据: \

查询是否有job为null的老师: \

查询指定日期的女老师: \

多条件查询: \

查询name末尾为e结尾的id: \

查询指定字符开头的: \

查询名字中带有z的: \

id倒叙排列: \

多值排序: \

男女分组: \

查询总记录数: \

limit分页查询: \


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