To check weather there is a null value or not, we use IS NULL or IS NOT NULL operators.
IS NULL : It is a condition used to select rows where the specific field is NULL.
Syntax:
SELECT * FROM table_name
WHERE column_name IS NULL;STUDENTS DEMO TABLE
| Roll_NO | Name | Total_Marks | Phone_Number |
| 1 | Arun | NULL | NULL |
| 2 | Rahul | 68 | 2147483647 |
| 3 | Nazim | 75 | 785764 |
| 4 | Alex | 65 | NULL |
| 5 | Pyush | 97 | NULL |
| 6 | Dev | 67 | 69483647 |
Example: To select the rows where the Phone_Number is NULL
SELECT * FROM students
WHERE Phone_Number IS NULL;The resultant table will be as shown below:
| Roll_NO | Name | Total_Marks | Phone_Number |
| 1 | Arun | NULL | NULL |
| 4 | Alex | 65 | NULL |
| 5 | Pyush | 97 | NULL |
IS NOT NULL : It is a condition used to select rows where the specific field is NOT NULL.
Syntax:
SELECT * FROM table_name
WHERE column_name IS NOT NULL;STUDENTS DEMO TABLE
| Roll_NO | Name | Total_Marks | Phone_Number |
| 1 | Arun | NULL | NULL |
| 2 | Rahul | 68 | 2147483647 |
| 3 | Nazim | 75 | 785764 |
| 4 | Alex | 65 | NULL |
| 5 | Pyush | 97 | NULL |
| 6 | Dev | 67 | 69483647 |
Example: To select the rows where the Phone_Number is NOT NULL
SELECT * FROM students
WHERE Phone_Number IS NULL;The resultant table will be as shown below:
| Roll_NO | Name | Total_Marks | Phone_Number |
| 2 | Rahul | 68 | 2147483647 |
| 3 | Nazim | 75 | 785764 |
| 6 | Dev | 67 | 69483647 |