Test: Quiz: Null Functions
Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer.
    Section 1
                   
        1.     With the following data in Employees (last_name, commission_pct, manager_id) what is the result of the following statement?
DATA:
King,null,null
Kochhar, null,100
Vargas, null, 124
Zlotkey,.2, 100
SELECT last_name, NVL2(commission_pct, manager_id, -1) comm
FROM employees ;
    Mark for Review
(1) Points
                   
           
    King, -1
Kochhar, -1
Vargas, -1
Zlotkey, .2
   
           
    Statement will fail.
   
           
    King, -1
Kochhar, 100
Vargas, 124
Zlotkey, .2
   
           
    King, -1
Kochhar, -1
Vargas, -1
Zlotkey, 100
(*)
   
                   
               
Correct        Correct
   
                   
        2.     The following statement returns 0 (zero). True or False?
SELECT 121/NULL
FROM dual;
    Mark for Review
(1) Points
                   
           
    True
   
           
    False (*)
   
                   
               
Correct        Correct
   
                   
        3.     Which function compares two expressions?     Mark for Review
(1) Points
                   
           
    NVL
   
           
    NULLIF (*)
   
           
    NVL2
   
           
    NULL
   
                   
               
Correct        Correct
   
                   
        4.     If quantity is a number datatype, what is the result of this statement?
SELECT NVL(200/quantity, 'zero') FROM inventory;
    Mark for Review
(1) Points
                   
           
    zero
   
           
    ZERO
   
           
    The statement fails (*)
   
           
    Null
   
                   
               
Correct        Correct
   
                   
        5.     Consider the following data in the Employees table:
(last_name, commission_pct, manager_id)
DATA:
King,null,null
Kochhar, null,100
Vargas, null, 124
Zlotkey,.2, 100
What is the result of the following statement:
SELECT last_name, COALESCE(commission_pct, manager_id, -1) comm
FROM employees ;
    Mark for Review
(1) Points
                   
           
    Statement will fail
   
           
    King, -1
Kochhar, 100
Vargas, 124
Zlotkey, .2
(*)
   
           
    King, -1
Kochhar, 100
Vargas, 124
Zlotkey, 100
   
           
    King, null
Kochhar, 100
Vargas, 124
Zlotkey, .2
   
                   
               
Correct        Correct
   
               
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