PL/SQL Section 4 Quiz

 1. Look at the following block:

DECLARE
  v_date DATE := SYSDATE;
BEGIN
  WHILE v_date < LAST_DAY(v_date) LOOP
    v_date := v_date + 1;
  END LOOP;
  DBMS_OUTPUT.PUT_LINE(v_date);
END;

If today's date is 17th April 2007, what will be displayed when this block executes?

Tandai untuk Ditinjau

(1) Point

17-Apr-2007

30-Apr-2007 (*)

01-May-2007

31-Dec-2007

Correct

---

2. Which statement best describes when a FOR loop should be used?

Tandai untuk Ditinjau

(1) Point

When the controlling condition must be evaluated at the start of each iteration

When testing the value in a Boolean variable

When the number of iterations is known (*)

Correct

---

3. When using a counter to control a FOR loop, which of the following is true ?

Tandai untuk Ditinjau

(1) Point

You must have exactly one counter but it is implicitly declared. (*)

You can have multiple counters, but you need at least one.

You don't need a counter; you can test for anything (for example, whether a BOOLEAN is TRUE or FALSE).

You must have exactly one counter and you must explicitly declare it.

Correct

---

4. The EXIT statement can be located anywhere inside a basic loop. True or False?

Tandai untuk Ditinjau

(1) Point

True (*)

False

Correct

---

5. A PL/SQL block contains the following code:
v_counter := 1;
LOOP
    EXIT WHEN v_counter=5;
END LOOP;
v_counter := v_counter + 1;

What is the value of V_COUNTER after the loop is finished?

Tandai untuk Ditinjau

(1) Point

This is an infinite loop; the loop will never finish. (*)

1

6. Which one of these tasks is best done using a LOOP statement?

Tandai untuk Ditinjau

(1) Point

Calculating and displaying the sum of all integers from 1 to 100 (*)

Testing if a condition is true, false, or null

Assigning a letter grade to a numerical score

Fetching and displaying an employee's last name from the database

Correct

---

7.

…BEGIN
<< Outer_loop >>
LOOP v_counter := v_counter+1;
EXIT WHEN v_counter>10;
<< Inner_loop >>
LOOP
...
EXIT Outer_loop WHEN v_total_done = 'YES';
-- Leave both loops
EXIT WHEN v_inner_done = 'YES';
-- Leave inner loop only
...
END LOOP Inner_loop;
...
END LOOP Outer_loop;
END;

In this code it is valid for each loop to have it's own EXIT statement.  True or False?

Tandai untuk Ditinjau

(1) Point

True (*)

False

Correct

---

8. What statement allows you to exit the inner loop at Point A in the following block?

DECLARE
 v_outer_done CHAR(3) := 'NO';
 v_inner_done CHAR(3) := 'NO';
BEGIN
 LOOP -- outer loop
   ...
   LOOP -- inner loop
    ...
    v_inner_done := 'YES';
    ... -- Point A
    ...
   END LOOP;
  ...
   EXIT;
  ...
 END LOOP;
END;

Tandai untuk Ditinjau

(1) Point

EXIT WHEN v_inner_done = 'YES'; (*)

WHEN v_inner_done = YES EXIT;

EXIT AT v_inner_done = 'YES';

EXIT   << inner loop>>

Correct

---

9. What clause will leave the outer loop at Point A?

DECLARE
  i INTEGER := 0;
BEGIN
   << i_loop >>
  WHILE i <= 10 LOOP
    i := i+1;
     << j_loop >>
      FOR j IN 1..5 LOOP
      _______ WHEN i = j*2; -- Point A
      DBMS_OUTPUT.PUT_LINE(i || j);
    END LOOP;
  END LOOP;
END;

Tandai untuk Ditinjau

(1) Point

EXIT   << outerloop>>

EXIT outerloop

EXIT j_loop

EXIT i_loop (*)

Correct

---

10. Which of the following statements are true about any of the PL/SQL conditional control structures such as IF ... , CASE … , and loops?

Tandai untuk Ditinjau

(1) Point

They allow the programmer to use logical tests to determine which statements are executed and which are not.

They allow a set of statements to be executed repeatedly (i.e. more than once).

All of these (*)

They determine a course of action based on conditions.

11. What is the correct form of a simple IF statement?

Tandai untuk Ditinjau

(1) Point

IF condition
THEN statement
ENDIF;

IF condition THEN statement;
END IF; (*)

IF condition THEN statement;

IF condition;
THEN statement;
END IF;

Correct

---

12. What is the correct name for CASE, LOOP, WHILE, and IF-THEN-ELSE structures ?

Tandai untuk Ditinjau

(1) Point

Control structures (*)

Memory structures

Cursor structures

Array structures

Correct

---

13. What will be displayed when the following block is executed?

DECLARE
  v_age NUMBER(3);
  v_gender VARCHAR2(6) := 'Female';
  v_status VARCHAR2(20);
BEGIN
  CASE
    WHEN v_age >= 18 AND v_gender = 'Male' THEN v_status := 'Adult Male';
    WHEN v_age >= 18 AND v_gender = 'Female' THEN v_status := 'Adult Female';
    WHEN v_age < 18 AND v_gender = 'Male' THEN v_status := 'Junior Male';
    WHEN v_age < 18 AND v_gender = 'Female' THEN v_status := 'Junior Female';
    ELSE v_status := 'Other Value';
  END CASE;
  DBMS_OUTPUT.PUT_LINE(v_status);
END;

Tandai untuk Ditinjau

(1) Point

Other Value (*)

Adult Male

Junior Female

Nothing will be displayed because V_STATUS is set to NULL.

Incorrect. Refer to Section 4 Lesson 2.

---

14. What will be the value of v_sal_desc after the following code is executed?

DECLARE
    v_salary NUMBER(6,2) := NULL;
    v_sal_desc VARCHAR2(10);
BEGIN
    CASE
       WHEN v_salary < 10000 THEN v_sal_desc := 'Low Paid';
       WHEN v_salary >= 10000 THEN v_sal_desc := 'High Paid';
    END CASE;
END;

Tandai untuk Ditinjau

(1) Point

Null

Low Paid

The code will fail and return an unhandled exception error to the host environment (*)

High Paid

Incorrect. Refer to Section 4 Lesson 2.

---

15. What will be the value of variable c after the following code is executed?

DECLARE
    a BOOLEAN := TRUE;
    b BOOLEAN := FALSE;
    c NUMBER;
BEGIN
    c :=
        CASE
            WHEN a AND b THEN 10
            WHEN NOT a THEN 20
            WHEN a OR b THEN 30
            ELSE 40
        END CASE;
END;

Tandai untuk Ditinjau

(1) Point

30 (*)

20

40

10