Multiple choice technology databases Which function return NULL when X = Y and X when it does not? NULLIF(X,Y) COALESCE(X,Y) ZEROIFNULL(X,Y) NULLIFZERO(X,Y) Reveal answer Fill a bubble to check yourself A Correct answer Explanation The NULLIF(X, Y) function compares two expressions. If they are equal, the function returns NULL. If they are not equal, it returns the first expression (X). COALESCE returns the first non-null value in its list.