MySQL简单语句登录然后输入密码查看数据库创建数据库推荐: 选中数据库查看当前所在的数据库删除数据库查看

mysql -u root -p   -h [主机名]
# 然后输入密码

查看数据库
```
show databases;
```

创建数据库

mysqladmin -u root -p123456 create test_base;

推荐:
```
create database test_base;    
```
选中数据库
```
use test_base;  
```
查看当前所在的数据库
```
status  (推荐)
select database();
```
删除数据库
```
drop database test_base;  
```
查看有哪些表
```
show tables;    
```

创建表

(推荐) create table test_table(num int, temperature float); 

create table `test_table`(`num` int, `temperature` float);

创建带字符串的表

create table TemperatureItem(name char(50), epic_id char(4), temperature float, count int, rssi tinyint, antena tinyint, coach_num int, timestamp bigint);

查看数据表有哪些项
```
desc test_table;
```
删除表
```
drop table test_table;  
```

表插入信息

insert coach_temp_table values (1, 20);

查看表中的所有信息
```
select * from coach_temp_table;  
```

只查某项

select coach_num from coach_temp_table;

删除某一条记录, where 后面是删除的条件子句
```
delete from coach_temp_table where coach_num = 1;  
```
加载.sql文件
```
source *.sql;
```

数据库添加用户,与修改密码

查看用户

select distinct concat('User: ''',user,'''@''',host,''';') as query from mysql.user;

添加用户

create user "用户名"@"IP地址" identified by "密码";  
# 比如
create user 'admin'@'%' identified by 'root';

授权

grant 权限类型 on 数据库名.表名 to '用户名'@'ip地址' identified by '用户密码' with grant option;  
grant all on *.* to 'admin'@'%';

更改密码

ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';  
# 推荐  
ALTER USER 'root'@'%' IDENTIFIED BY '123456';

删除用户
```
drop user admin;
```