Basic statement of database operation

Take the book back , After understanding the deployment 、 link mysql after , Want to write code , You need to know the basic statements of database operation in advance , Let's start with ：

mysql -u xiaochun -p

Input password , land ;

show databases;

Display all databases , No, 【spring】 Database , Create a ;

use spring;

Use 【spring】 database ;

mysql> create table user(id integer primary key auto_increment,
    -> name varchar(60) not null,
    -> age integer(3),
    -> sex varchar(1));
Create table , And initialize the field ;

show tables;

View under this library , All the watches ;

alter table user rename to student;

Modify the name of the table 【user】 by 【student】;

desc student;

View table structure ;

drop table user;

insert into student values(1,'xiaoming',18,'1');

Add data ;

insert into student(id,name,age,sex) values(2,'xiaozhang',16,'2');

Add data ;

insert into student(id,name,age,sex) values(null,'xiaozhang',16,'2');

Add data , When id Pass in null when , The primary key increases automatically ;

select * from student;

View the data ;

select name,age from student where sex='2' and age<19 order by name;

Conditional query sorting ;

Delete the name 【user】 Table of ;

 

Attach a screenshot of the Internet query ：

 

The preparations are complete , Next chapter springboot .