text: CREATE TABLE Categories
  (
  	Id INT PRIMARY KEY IDENTITY,
  	[Name] NVARCHAR(30) NOT NULL
  )
  
  CREATE TABLE Items
  (
  	Id INT PRIMARY KEY IDENTITY,
  	[Name] NVARCHAR(30) NOT NULL,
  	Price DECIMAL(15, 2) NOT NULL,
  	CategoryId INT FOREIGN KEY REFERENCES Categories(Id) NOT NULL
  )
  
  CREATE TABLE Employees
  (
  	Id INT PRIMARY KEY IDENTITY,
  	FirstName NVARCHAR(50) NOT NULL,
  	LastName NVARCHAR(50) NOT NULL,
  	Phone CHAR(12) NOT NULL,
  	Salary DECIMAL(15, 2) NOT NULL
  )
  
  CREATE TABLE Orders
  (
  	Id INT PRIMARY KEY IDENTITY,
  	[Datetime] DATETIME NOT NULL,
  	EmployeeId INT FOREIGN KEY REFERENCES Employees(Id) NOT NULL
  )
  
  CREATE TABLE OrderItems
  (
  	OrderId INT FOREIGN KEY REFERENCES Orders(Id) NOT NULL,
  	ItemId INT FOREIGN KEY REFERENCES Items(Id) NOT NULL,
  	Quantity INT 
  
  	PRIMARY KEY (OrderId, ItemId)
  	CONSTRAINT CH_Quantity CHECK(Quantity >= 1)
  )
  
  CREATE TABLE Shifts
  (
  	Id INT IDENTITY,
  	EmployeeId INT FOREIGN KEY REFERENCES Employees(Id),
  	CheckIn DATETIME NOT NULL,
  	CheckOut DATETIME NOT NULL
  
  	PRIMARY KEY (Id, EmployeeId)
  )
  
  	ALTER TABLE Shifts
  	ADD CONSTRAINT CH_CHECKOUT CHECK(CheckIn < CheckOut)