COALESCE

Return the initial non-null value from a list.

SELECT COALESCE(NULL, NULL, NULL, ‘W3Schools.com’, NULL, ‘Example.com’);

Definition and Usage

The COALESCE() function retrieves the first non-null value from a list of arguments.

COALESCE(val1, val2, …., val_n)

Parameter	Description
val1, val2, val_n	Required. The values to evaluate

Works in:

From MySQL version 4.0

Retrieve the initial non-null value from a list.

SELECT COALESCE(NULL, 1, 2, ‘W3Schools.com’);