IFNULL

Syntax

IFNULL(expr1, expr2)

Description

The IFNULL() function returns expr1 if expr1 is not NULL; otherwise, it returns expr2. The return value of IFNULL() is a number or string, depending on the context in which it is used.

The default return type of IFNULL() is determined as follows:

Expression	Return type
expr1 or expr2 returns a string.	String
expr1 or expr2 returns a floating-point value.	Float
expr1 or expr2 returns an integer.	Integer

If both expr1 and expr2 are strings and either of them is case-sensitive, the result is case-sensitive.

Examples

SELECT IFNULL('abc', null), IFNULL(NULL+1, NULL+2), IFNULL(1/0, 0/1);
+---------------------+------------------------+------------------+
| IFNULL('abc', null) | IFNULL(NULL+1, NULL+2) | IFNULL(1/0, 0/1) |
+---------------------+------------------------+------------------+
| abc                 |                   NULL |           0.0000 |
+---------------------+------------------------+------------------+
1 row in set (0.001 sec)