text: CREATE TABLE Persons2
  (
  P_Id int NOT NULL,
  LastName varchar(255) NOT NULL,
  FirstName varchar(255),
  Address varchar(255),
  City varchar(255),
  CONSTRAINT uc_PersonID UNIQUE (P_Id)
  );
  
  CREATE TABLE Persons3
  (
  P_Id int NOT NULL,
  LastName varchar(255) NOT NULL,
  FirstName varchar(255),
  Address varchar(255),
  City varchar(255),
  CONSTRAINT pk_PersonID PRIMARY KEY (P_Id,LastName)
  );
  
  
  CREATE TABLE Orders
  (
  O_Id int NOT NULL,
  OrderNo int NOT NULL,
  P_Id int,
  PRIMARY KEY (O_Id),
  CONSTRAINT fk_PerOrders FOREIGN KEY (P_Id)
  REFERENCES Persons2 (P_Id)
  );
  