COALESCE

Coalesce is shorthand for a frequently used variation of CASE.

Syntax

COALESCE (value1, value2, value3)
is equivalent to
CASE
WHEN value1 IS NOT NULL THEN value1
WHEN value2 IS NOT NULL THEN value2
ELSE value3
END

Example

SELECT name, job_title, COALESCE (salary, commission, subsistence) 
FROM job_assignments