Student
	fisrt name
	last name
	address
	phone

- Tao ra cau truc bang trong database nhu the nao
- Table (bang) => Student (chuan dat ten: a-zA-Z0-9 hoac _)
	fisrt name => firstname: kieu du lieu => string => nvarchar(30)
	last name => lastname: kieu du lieu => string => nvarchar(30)
	address: string => nvarchar(200)
	phone: string => nvarchar(15)
- Trien khai phat trien tren du an.
- dau tien : database => T2008A

Student2
	firstname
	lastname
	address
	phone
	rollno: primary key => nvarchar(20)

Product
	- id: int => tu tang => identity(1, 1)
	- title => nvarchar(150)
	- content => text
	- thumbnail => nvarchar(500)
	- amount => int => >= 0
	- price => float => >= 0

- created_at & updated_at =>

------- Basic
create table Student(
	firstname nvarchar(30),
	lastname nvarchar(30),
	address nvarchar(200),
	phone nvarchar(20)
)

-- Them du lieu vao
insert into Student(firstname, lastname, address, phone)
values
('Diep', 'Tran Van', 'Nam Dinh', '123456789')

insert into Student(firstname, lastname, address, phone)
values
('A', 'Tran Van', 'Hai Duong', '123456789'),
('B', 'Tran Van', 'Ha Noi', '123456789')

select * from Student
-------- basic 1: primary key => khoa chinh => column => gia tri la duy nhat
create table Student2 (
	rollno nvarchar(20) primary key,
	firstname nvarchar(30),
	lastname nvarchar(30),
	address nvarchar(200),
	phone nvarchar(20)
)
select * from Student2

insert into Student2(rollno, firstname, lastname, address, phone)
values
('R002', 'Diep', 'Tran Van', 'Nam Dinh', '123456789')

insert into Student2(rollno, firstname, lastname, address, phone)
values
('R003', '', '', '', '')

insert into Student2(rollno, firstname, lastname, address, phone)
values
('', 'Diep', 'Tran Van', 'Nam Dinh', '123456789')

----- error chuong trinh
insert into Student2(rollno, firstname, lastname, address, phone)
values
(null, 'Diep', 'Tran Van', 'Nam Dinh', '123456789')

------ basic 2 - nang cao
create table Product (
	id int primary key identity(1,1),
	title nvarchar(150) not null,
	content text,
	amount int,
	price float
)

alter table Product
add created_at datetime;

alter table Product
add updated_at datetime

alter table Product
add abc datetime

select * from Product

alter table Product
drop column abc

alter table Product
add constraint check_amount check (amount >= 0)

alter table Product
add constraint check_price check (price >= 0)

insert into Product(title, amount, price, created_at, updated_at)
values
('A', 1, 10, '2020-08-22 10:5:30', '2020-08-22 10:5:30')

delete from Product