SQL IS NULL Clause with example

SQL IS NULL Clause

• NULL is a special value that signifies 'no value'.
• Comparing a column to NULL using the = operator is undefined.
• Instead, use WHERE IS NULL or WHERE IS NOT NULL.

The SQL WHERE IS NULL syntax

The general syntax is:

1. SELECT column-names FROM table-name WHERE column-name IS NULL

The general not null syntax is:

1. SELECT column-names FROM table-name WHERE column-name IS NOT NULL

SQL WHERE IS NULL Examples

 1) Example of is null Clause 

mysql> select name from person where age is null;
+------+
| name |
+------+
| debo |
| NULL |
| NULL |
+------+
3 rows in set (0.00 sec)

2) Example of Is not null

 mysql> select name from person where age is not null;
+-----------------+
| name            |
+-----------------+
| subham ball     |
| jit             |
| sajal           |
| sourav biswas   |
| sajal           |
| chayan das      |
| shantanu biswas |
| sudip saha      |
| mono            |
| monojit         |
+-----------------+
10 rows in set (0.00 sec)