Categories:

Conditional Expression Functions

NVL

If expr1 is NULL, returns expr2, otherwise returns expr1.

Aliases

IFNULL

Syntax

NVL( <expr1> , <expr2> )

Arguments

expr1

The expression to be checked to see whether it’s NULL.

expr2

If expr1 is NULL, this expression is evaluated and its value is returned.

Collation Details

• The collation specifications of all input arguments must be compatible.

• The collation of the result of the function is the highest-precedence collation of the inputs.

Examples

Call NVL with both NULL and non-NULL values for the first expression:

SELECT NVL('food', 'bard') AS col1, NVL(NULL, 3.14) AS col2;

+------+------+
| COL1 | COL2 |
+------+------+
| food | 3.14 |
+------+------+