不得不知道的mysql的基本操作
MYSQL的基本语句 1.Createdatabase 数据库名; 创建数据库类型 2.show database; 显示所有数据库信息 3.use 数据库名; 选择数据库 4.drop database 数据库名; 删除数据库 5.create table 表名 (字段名1 类型, 字段名2 类型) 创建表 6.show cloums from
MYSQL的基本语句
1.Create database 数据库名;
创建数据库类型
2.show database;
显示所有数据库信息
3.use 数据库名;
选择数据库
4.drop database 数据库名;
删除数据库
5.create table 表名 (字段名1 类型, 字段名2 类型)
创建表格
6.show cloums from 数据库名.数据表名
显示指定的表结构
7.desc 表名列名;
显示表中一个字段的结构
8.alter table 表名 操作的关键字 具体操作
修改表
9.rename table 旧表名 to 新表名
改表名字
10.Drop table 表名;
删除表的名字
11.insert into 表名(字段名1,字段名2) values (对应的值1,对应的值2);
插入表
12.Concat()联合多列
使用concat函数可以联合多个字段,构成一个总的字符串
Select concat(name ,“:”,age) from user;
13.limit限定查询行数
Select * from 表名 limit 2,3
意思是从第二条记录连续读3条
14.sum()求和
15.Update 表名 set 字段名=对应的值 where 条件
更新表
16. delete from 表名 where 条件
删除表中的记录
17.

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