mysql基础----)基本命令与13道练习_MySQL
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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