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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