title: SQL error code: 1364 Field 'CustomerNumber' doesn't have a default value
body: <pre><code>CREATE TABLE CUSTOMER(
  CustomerNumber int NOT NULL PRIMARY KEY,
  CustomerFirstName char(30) NOT NULL,
  CustomerLastName char(30) NOT NULL,
  Phone char(12) NOT NULL
  );
  
  CREATE TABLE ENROLLMENT( 
  CourseNumber int NOT NULL, 
  CustomerNumber int NOT NULL, 
  AmountPaid float(2) NOT NULL, 
  CONSTRAINT pk_ENROLLMENT PRIMARY KEY (CustomerNumber, CourseNumber),
  CONSTRAINT ENROLLMENTS_fk FOREIGN KEY (CustomerNumber) 
      REFERENCES CUSTOMER(CustomerNumber), 
  CONSTRAINT fk_ENROLLMENT FOREIGN KEY (CourseNumber) 
      REFERENCES COURSE(CourseNumber) 
      ON DELETE CASCADE ON UPDATE CASCADE 
  ); 
  
  INSERT INTO CUSTOMER(CustomerNumber, CustomerFirstName, CustomerLastName, Phone)
  VALUES (992, 'Steve', 'Johnson', '631-998-2244');
  INSERT INTO CUSTOMER(CustomerNumber, CustomerFirstName, CustomerLastName, Phone)
  VALUES (998, 'Jane', 'Lovegood', '516-777-0033');
  INSERT INTO CUSTOMER(CustomerNumber, CustomerFirstName, CustomerLastName, Phone)
  VALUES (987, 'John', 'Lovegood', '516-777-2888');
  
  INSERT INTO ENROLLMENT(CourseNumber)
  SELECT CourseNumber
  FROM COURSE
  WHERE Course = 'Statistics' LIMIT 1;
  INSERT INTO ENROLLMENT(CustomerNumber, AmountPaid)
  SELECT CustomerNumber, 600.00
  FROM CUSTOMER
  WHERE CustomerLastName = 'Johnson' LIMIT 1;
  </code></pre>