NULLIF

NULLIF compares one expression with another. It returns NULL when the expressions are equal, or the first expression when they are not.

Return Value

Data type of the first argument

Syntax

NULLIF(expr1, expr2)

Arguments

expr1 is the base expression. It cannot be a literal null.

expr2 is the expression to compare with the base expression.

Example

NULLIF('red', 'Red') returns the value red.