Multiple choice technology databases

SELECT NULLIF(NULL,'testing') FROM DUAL ;

  1. testing

  2. True

  3. null

  4. error

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In Oracle SQL, the NULLIF(expr1, expr2) function compares two expressions. If they are equal, it returns null; otherwise, it returns expr1. Oracle raises a syntax or validation error if the first argument is a literal NULL.