/*
mysql> SELECT ExamID,SustainedOn,Comments FROM Exam
-> WHERE Comments IS NULL;
+--------+-------------+----------+
| ExamID | SustainedOn | Comments |
+--------+-------------+----------+
| 1 | 2003-03-12 | NULL |
+--------+-------------+----------+
1 row in set (0.00 sec)
*/
/* Prepare the data */
DROP TABLE Exam;
CREATE TABLE Exam (
ExamID INT NOT NULL PRIMARY KEY,
SustainedOn DATE,
Comments VARCHAR(255)
)TYPE = InnoDB;
/* Insert data for testing */
INSERT INTO Exam (ExamID,SustainedOn,Comments) VALUES (1,'2003-03-12',NULL);
INSERT INTO Exam (ExamID,SustainedOn,Comments) VALUES (2,'2004-03-13','C# test');
INSERT INTO Exam (ExamID,SustainedOn,Comments) VALUES (3,'2005-03-11','JavaScript Test');
/* Real command */
SELECT ExamID,SustainedOn,Comments FROM Exam
WHERE Comments IS NULL;