List of top Informatics Practices Questions asked in CBSE Class XII

Consider the DataFrame Scholarship shown below:

Answer the following questions:

Write suitable SQL query for the following:

I. To display the value of 17².

II. To display the day part of the dates in the Hire_Date column of the Employee table.

III. To display the maximum value of the Bill_Amount column in the Bill table.

IV. To remove leading and trailing spaces from the Location column in the Branch table.

V. To display total salary from tot_sal column in Employees table.

Write suitable SQL query for the following:

I. To display only the date part from the date/time expression '2026-01-01 10:10:10'

II. To convert all customer names from the Cust_Name column to lowercase in the Customer table.

III. To extract the first 4 characters from the City_Name column in Location table.

IV. To display the name of the city from the CITY column in EVENT table, after removing leading spaces.

V. To find the average salary from Salary column in Employees table.

Consider the following tables:

Table 1: TEACHER, which stores Teacher ID (TID), Teacher Name (TName), Experience(Experience) and City (City) that they live in.

Table 2: SUBJECT, which stores Subject ID (SID), Subject Name (SubName) and ID of the teacher (TID) teaching that Subject.

Write appropriate SQL query for the following:

(I) Delete the record of the subject whose TID is equal to 4.

(II) Display the names of teachers who have more than 5 years of experience and who stay in Nagpur.

(III) Display subject names along with their teacher names.

Shalini, who works as a database designer in the hotel industry, has created a table named Guest to keep track of guest details as shown below:

Table : Guest

Write a suitable SQL query for the following:

I. Display last 3 characters of guest name in upper case.

II. Display the name of the guest along with the day name of check-in date.

III. Display the remainder when charges are divided by 1000.

IV. Extract and display three characters, starting from the second character, of each guest name.

My Solutions Pvt. Ltd. is a reputed software development and IT consulting firm. The company's head office is located in Mysuru, and it has a regional office in Chennai. The Mysuru office comprises four departments: Human Resources, Research, Design and Technical Support.

The distances between these departments and between Mysuru and Chennai are as follows:

The number of computers in each department/office is as follows:

As a network engineer, you have to propose solutions for various queries listed from I to V.

I. Identify the most suitable department to install the main server in the Mysuru office. Justify your answer with a valid reason.

II. Create a cable layout design to establish Wired network connectivity between the departments in the Mysuru Office.

III. Suggest the appropriate network device to connect multiple computers within the Research department.

IV. What type of network (LAN, MAN, WAN) would best connect the Mysuru and Chennai office?

V. Which device should be used if the signal strength weakens while transmitting data between the Human Resources and Technical Support departments due to the long distance between them?

(i) Write an SQL statement to create a table named PRODUCTS with the following specifications:

(ii) Write an SQL query to increase the price of all items by 100, whose product category is Grocery, in the table PRODUCTS.

Consider the table LIBRARY as given below.

(I) Which attribute(s) can be considered as the Candidate keys(s)? Justify your answer.

(II) Write an SQL query to insert a new record with the following values: BookId: 501, Title: AI for ALL, Genre: Technology, Price: 589

(III) Write an SQL query to add a new column Author that is a character data type of size 20.

A CSV file named customer.csv contains records of customers. The first row of the file represents the header. Sample data from the file is shown below:

Name, Age, City
Rudra,17,Kolkata
Divya,19,Dehradun
Nabeel,22,Lucknow

Write a Python program to import data from the CSV file into a Pandas DataFrame named DF and display the last two rows.

Consider the following table and write the output of the following SQL Queries.

Table : ORDERS

Write the output of the following SQL Queries:

I. SELECT CUSTOMERNAME FROM ORDERS WHERE DISCOUNT IS NOT NULL;

II. SELECT CUSTOMERNAME, DISCOUNT FROM ORDERS WHERE DISCOUNT BETWEEN 5 AND 10;

III. SELECT MONTHNAME(ORDERDATE) FROM ORDERS WHERE ORDERDATE IS NOT NULL;

IV. SELECT ORDERID, DAY(ORDERDATE) FROM ORDERS;

Ms. Anjali, a data analyst, has been assigned the task of creating a histogram to display the age distribution of ten participants in a workshop. She has been provided with the following list of their ages:

Ages = [22, 25, 24, 28, 30, 24, 29, 27, 21, 23]

She has started writing a Python program for it. However, the code is incomplete. Help her complete the program by filling in the missing parts, so that the histogram as shown below is displayed.

import matplotlib.pyplot as plt
Ages = [22, 25, 24, 28, 30, 24, 29, 27, 21, 23]
binsize=[20,22,24,26,28,30]
plt.________(Ages, bins=binsize, edgecolor = 'black', label = 'Participants')  # Statement-1
______.xlabel('Age')  # Statement-2
plt.ylabel('Number of Participants')
plt.title("Age Distribution")
plt.________  # Statement-3
___________  # Statement-4

I. Write the suitable code for the blank space in the line marked as Statement-1 which plots the histogram.

II. Fill in the blank in Statement-2 to use the correct alias of the required module to set the label on x axis.

III. Fill in the blank in Statement-3 with the correct Python code to display the legend on the graph.

IV. Fill in the blank in Statetment-4 with the appropriate Python code to display the graph.

(a) What is data protection?

(b) Mention any two precautionary measures one can take to avoid the risk of cybercrime.

Mandeep received an email stating he won a lottery though he had never participated in any such event. He was asked to provide bank details to process the amount. Mandeep provided the required details but within next few minutes ₹ One lakh was debited from his account.

Answer the following questions based on the given case study:

(i) Mandeep is the victim of which type of cybercrime?

(ii) Other than email, mention any two common methods through which this type of cybercrime is being committed these days.

(iii) Name one law that safeguards the rights of Internet users in India.

Differentiate between add-ons and plug-ins in a web browser.

Write the output of the following code:

import pandas as pd
s1 = pd.Series ([1, 2, 3], index = ['a','b','c'])
s2 = pd.Series ([4, 5, 6], index = ['b','c','d'])
print (s1 + S2)

Niharika wants to create a Pandas Series using a NumPy array with three elements 'a', 'b', and 'c', and assign custom indexes 'first', 'second' and 'third'. Help her complete the code below.

import pandas as pd
import ______ as np
arr = np._____ (['a' , 'b' , 'c'])
s = pd._____(arr,_____=['first','second','third'])
print(s)

Write a Python program to create and display a Pandas Series as shown below:

The index labels are the names of the months – July, Aug, Sept, Oct.

The corresponding scalar values are the number of days in these respective months – 31, 31, 30, 31.

Write SQL queries to perform the following:

(I) Display the month (in numeric form) of the date '2026-01-01'.

(II) Display only the year part from the date '2026-01-01'.

Define the following terms with respect to RDBMS:

a. Domain

b. Tuple

Briefly explain the purpose of Boolean Indexing with respect to DataFrames. Support your answer with a suitable example.

Anjana had created a website using free design elements sourced from different creators online. She then published the site for public access but did not mention the source of the design elements used.

(i) Identify one possible violation of IPR in this situation,

(ii) Name any two licensing models that allow legal reuse of digital creative work with conditions.

List any two characteristics of Pandas library in Python.

Assertion (A): The output of the SQL query SELECT COUNT (name) FROM students; will differ from the output of SELECT COUNT (*) FROM students; if there are some NULL values in the name column.

Reason (R): COUNT(column_name) returns the count of NON NULL values in that column, whereas COUNT(*) returns the number of records in the table.

Explain the role of the following network devices in a network:

(I) Modem

(II) Gateway

Assertion (A): Pandas DataFrame can store values of multiple data types in multiple Columns.

Reason (R): DataFrames are implemented using 2D arrays, which allows only numeric values.