COALESCE (Azure Stream Analytics)

Evaluates the arguments in order and returns the value of the first expression that initially does not evaluate to NULL.

Syntax

COALESCE ( expression1, expression2,  [ ,…n ] )

Arguments

expression

An expression of any type.

Return Types

The type of the first non-null expression.

Examples

SELECT COALESCE(a, b) AS result FROM input

Expression	Result
COALESCE(0, ‘a’)	0
COALESCE(NULL, ‘a’)	‘a’
COALESCE(NULL, NULL)	null
COALESCE(NULL, NULL, 2, NULL)	2