title: ORA-00907: missing right parenthesis
body: <pre><code>CREATE TABLE Persons (
    P_Id int NOT NULL,
    LastName varchar(255) NOT NULL,
    FirstName varchar(255),
    PRIMARY KEY (P_Id)
  )
  
  CREATE TABLE Orders (
    O_Id int NOT NULL PRIMARY KEY,
    OrderNo int NOT NULL,
    P_Id int FOREIGN KEY REFERENCES Persons(P_Id)
  )
  </code></pre>
  
  <p>I am getting an error while creating Table Orders:</p>
  
  <blockquote>
    <p>ORA-00907: missing right parenthesis</p>
  </blockquote>