CBSE Question Paper 2007 class 12 Informatics Practices

General Instructions:

• This question paper is divided into 3 sections.
• Section A consists of 30 marks.
• Section B and Section C are of 20 marks each.
• Answer the questions after carefully reading the text.

Section-A

1. Answer the following questions:

(a) Define (i) Freeware (ii) Shareware (2)
(b) Write one point of difference between front end and back end with one example of each. (2)
(c) Write one example each of “one to many” and “many to many” relationships between two entity sets. (2)
(d) What is the purpose of Data Mining? (2)
(e) During System Development Life Cycle, in which phase is the scope and true nature of problem determined? Explain in brief with the help of an example. (2)

2. Answer the following questions:

(a) How many value(s) does a Procedure and a Function return? (2)
(b) Distinguish between Single Document Interface and Multiple Document Interface. Write one example each of SDI and MDI type application. (2)
(c) What is Selection statement? Name any two selection statements that VB provides. (2)
(d) What are Events? What are Event Procedures? How are they related? (2)
(e) What is a Bound Control? Name any two data-aware properties of bound controls. (2)

3. Answer the following questions:

(a) Which statement must be present in a simple loop (Loop. Endloop) so that it does not become an infinite loop? (1)
(b) Suggest parameters mode (IN/OUT/IN OUT) for the following: (1)
(i) Parameter can be used as a normal variable.
(ii) Passed value must not get changed.

(c) Write two points of differences between SQL and PL/SQL. (2)
(d) How are triggers similar to Constraints? Write one point. (2)
(e) What is the purpose of cursor in PL/SQL? Name the types of cursors used in PL/SQL. (2)
(f) Why do we use Rollback statement? Explain in brief with the help of an example. (2)

Section-B

4. Read the following case study and answer the questions that follow:
ABC Company has developed the following interface to enter and display data related to Income tax of employees.

The form details of the above form are given in the following table:

Write code to implement the following:

(a) When the form loads text boxes for Income tax, Education Tax, Surcharge and Total Tax Amount should be disabled. They should be enabled only when Calculate command button is clicked. (2)
(b) Taxable Income entered should be numeric data. (2)
(c) When the user clicks the Clear command button, textboxes EmpCode and EmpName should be set to blank and other textboxes should be set to zero. (2)
(d) When Calculate command button is clicked, Income tax, Education Tax, Surcharge and Total Tax (sum of Income Tax, Education Tax, Surcharge) is displayed in their respective text boxes based on the following criterion. (4)

5. Answer the following questions:

(a) How many times will the following loop execute? (2)
1 = 6
Do While I > = -1
I -1-2
Print I
Loop

(b) Write the output that the following code segment will generate (2)

String1 = “Class XII”
String2 = “XI”
Print String1 + String2
print InStr (String1, String2)
Mid (LCase(String1), 6, 3)
Print Int(4.7) + Len(String 2)

(c) Rewrite the following code using If Elself 2
Select Case Code
Case Is > 45
Message1 = “Ersor”
Case10 To 20
Message 1 = “Accounts”
Case 21 To 30
Message 1 = “Personnel”
Case 31 To 45
Message 1 = “EDP”
Case Else
Message 1 = “Access Denied”
End Select

(d) Write a function that receives two integers as arguments and returns the following: 4
0 if both are equal
– 1 if first is greater than the second
1 if second is greater than the first

Section-C

6. Read the questions given below and answer accordingly:

(a) Write PL/SQL cursor declaration to store Employee code(EMPNO), Employee name(ENAME) of employees from Emp table who are located (LOC) in Delhi. (2)

(b) Write the output produced by the following code in PL/SQL (2)

declare
cnt number;
num number;
begin
cnt: – 8;
num : = 4;
while cnt>4 loop
num : = num-2;
cnt: = cnt-1;
if cnt>4 then
dbms_output.put_line(cnt);
end if;
end loop;
dbms_output.put_line(num);
end;

(c) Find error(s) in the following PL/SQL code and rewrite the correct code after underlining the corrections made. (2)

DECLARE
CTR NUMBER;
SUM1 NUMBER;90/1 6
BEGIN
CTR: = 0;
SUM1: = 0;
LOOP
SUM1: = SUM1 + CTR;
PRINT(TO_CHAR(SUM1));
CTR: = CTR-2;
IF CTR > 2 THEN
EXIT;
END LOOP;

(d) Create a procedure called Select employee that selects the first name, last name, join date, and salary for employee with employee code 100 from EMP table into variables and displays values stored in these variables.

Table Emp consists of fields with field names: ID,
FIRST_NAME, LAST_NAME, JOIN_DATE, SALARY 4

7. Answer questions based on the table Student given below:

Table: Student

(a) Write SQL command to display Roll numbers, names, Total marks and grades of all the students in “Nonmedical” stream sorted by Total marks in descending order. (2)

(b) Write SQL command to create a view consisting of all students in “Medical” stream and who have scored “A” grade. (2)

(c) Write PL/SQL Procedure that takes in Student’s Roll number as a parameter and increases Total marks of that student by 2% (as he/she is a Sports person.) (3)

(d) Create a Trigger to display the name and stream of Student(s) whose record(s) is/are being deleted from the Student table. (3)