sql操作api

最新推荐文章于 2024-08-03 10:59:37 发布

原创最新推荐文章于 2024-08-03 10:59:37 发布 · 269 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#sql #数据库 #mysql

本文档详细记录了SQL语句的基础操作，包括数据库和表的创建、修改与删除，以及数据的插入、更新与查询等核心操作。通过一系列实用的例子展示了如何使用DDL和DML语句来管理和操作数据。

sql语句学习，记录。

-- ddl
create database test;
show databases;
create database if not exists test;
create database test character set utf8;
show create database test;
alert database test default character set gbk;
drop database test;
select database();
use test;
create table student(id int,name varchar(10),age int,birthday date,sex char(1));
show tables;
desc student;
show create table student;
create table student1 like student;
drop table student1;
drop table if exists student1;
alter table student add remark varchar(20);
alter table student modify remark varchar(100);
alter table student change remark intro varchar(20);
alter table student drop remark;
rename table student to student2;
alter table student character set gbk;
-- dml
insert into student (id,name,age)values(1,"test",12);
select * from student;
insert into student values(2,"ivan",12);
insert into student1 select * from student;
insert into student1(id,name,sex) select id,name,sex from student;
update student1 set sex='女';
update student set sex='男' where id=2;
delete from student where id=3;
delete from student;
truncate table student;
select * from student;
select age from student;
select name as 姓名,age as 年龄,sex as 性别 from student;
select distinct name,age from student;
select match+english 总成绩 from student;
select name 姓名,age+10 as 年龄 from student;