What is NullIf function in sql

NULLIF function returns null value if the two specified expressions are equivalent. NULLIF is equivalent to a searched CASE function in which the two expressions are equal and the resulting expression is NULL. NULLIF returns the first expression if the two expressions are not equivalent. If the expressions are equivalent, NULLIF returns a null value of the type of the first expression.
Syntax of NULLIF Function is given below:-
NULLIF (expression1 , expression2)

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