阿里SQL学习笔记1——Task1

本笔记为阿里云天池龙珠计划SQL训练营的学习内容，链接为：https://tianchi.aliyun.com/specials/promotion/aicampsql；

内容会做在一个思维导图中——MySQL笔记 - GitMind

Task1作业

1.create table Addressbook
(regist_no interger not null,
name varchar(128) not null,
address varchat(256) not null,
tel_no char(10),
mail_address char(20),
 primary key (regist_no interger)
);

2. alter table Addressbook add  postal_code char (8) not null;

3.drop table Addressbook;

4.删除的表无法恢复，得重新创建

create table Addressbook
(regist_no interger not null,
name varchar(128) not null,
address varchat(256) not null,
tel_no char(10),
mail_address char(20),
 primary key (regist_no interger)
);