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Class XI Informatics Practices (065): Practice Sample Paper 2025-26

Time: 3 hoursMaximum marks: 70Original Aimify paper in the CBSE pattern

General instructions

  1. This question paper contains 37 questions in five sections, A to E. All questions are compulsory.
  2. Section A has 21 questions of 1 mark each (multiple choice, including 2 Assertion-Reason questions).
  3. Section B has 7 very short answer questions of 2 marks each.
  4. Section C has 4 short answer questions of 3 marks each.
  5. Section D has 2 case-based questions of 4 marks each.
  6. Section E has 3 long answer questions of 5 marks each.
  7. There is no overall choice. Internal choices are given in some questions; attempt only one of the alternatives in such questions.
  8. All programming questions are to be answered in Python only. All SQL commands are to be written for MySQL.
Blueprint (unit-wise marks)
UnitMarks
Unit 1: Introduction to Computer System10
Unit 2: Introduction to Python25
Unit 3: Database Concepts and SQL30
Unit 4: Introduction to Emerging Trends5
Total70

Section A

Questions 1 to 21 carry 1 mark each. Questions 20 and 21 are Assertion-Reason questions.

  1. 1 markComputer System

    How many bytes are there in 2 KB?

    1. 2000
    2. 1024
    3. 2048
    4. 4096
    Marking scheme

    (c) 2048

    1 KB = 1024 bytes, so 2 KB = 2048 bytes.

  2. 1 markComputer System

    Which of the following memories loses its contents when the power is switched off?

    1. ROM
    2. Hard disk
    3. RAM
    4. Pen drive
    Marking scheme

    (c) RAM

  3. 1 markComputer System

    Which of the following is system software?

    1. A school's fee-management package
    2. A device driver for a printer
    3. A spreadsheet program
    4. A photo-editing app
    Marking scheme

    (b) A device driver for a printer

  4. 1 markComputer System

    A file deleted from a hard disk can often be recovered because:

    1. deletion erases the data immediately
    2. only the file's entry is removed; the data stays until it is overwritten
    3. every file is automatically copied to the cloud
    4. the operating system encrypts deleted files
    Marking scheme

    (b) only the file's entry is removed; the data stays until it is overwritten

  5. 1 markPython

    Which of the following is a valid identifier in Python?

    1. 2ndTerm
    2. total-marks
    3. _score
    4. for
    Marking scheme

    (c) _score

    An identifier cannot start with a digit, cannot contain a hyphen and cannot be a keyword.

  6. 1 markPython

    What will print(17 // 5, 17 % 5) display?

    1. 3.4 2
    2. 3 2
    3. 3 3
    4. 4 2
    Marking scheme

    (b) 3 2

  7. 1 markPython

    Which of the following data types is immutable?

    1. list
    2. dictionary
    3. string
    4. All of these
    Marking scheme

    (c) string

  8. 1 markPython

    L = [10, 20, 30, 40]. Which statement places 25 between 20 and 30?

    1. L.append(25)
    2. L.insert(2, 25)
    3. L.insert(3, 25)
    4. L.add(25)
    Marking scheme

    (b) L.insert(2, 25)

  9. 1 markPython

    D = {"pen": 10, "ink": 25}. Which statement removes the key "pen" from D?

    1. D.remove("pen")
    2. del D["pen"]
    3. D.pop()
    4. D.clear("pen")
    Marking scheme

    (b) del D["pen"]

  10. 1 markPython

    Assuming import numpy as np, which statement creates a NumPy array from the list [4, 8, 12]?

    1. np.list([4, 8, 12])
    2. np.create([4, 8, 12])
    3. array.np([4, 8, 12])
    4. np.array([4, 8, 12])
    Marking scheme

    (d) np.array([4, 8, 12])

  11. 1 markSQL

    The number of tuples (rows) in a relation is called its:

    1. degree
    2. cardinality
    3. domain
    4. attribute
    Marking scheme

    (b) cardinality

  12. 1 markSQL

    A candidate key that is not chosen as the primary key is called:

    1. an alternate key
    2. a foreign key
    3. a composite key
    4. a domain
    Marking scheme

    (a) an alternate key

  13. 1 markSQL

    Which SQL command adds a new column to an existing table?

    1. UPDATE
    2. INSERT
    3. ALTER TABLE
    4. MODIFY TABLE
    Marking scheme

    (c) ALTER TABLE

  14. 1 markSQL

    The DELETE command belongs to which category of SQL commands?

    1. DDL
    2. DML
    3. DQL
    4. None of these
    Marking scheme

    (b) DML

  15. 1 markSQL

    Which condition displays the rows in which Fees has not been entered?

    1. Fees = NULL
    2. Fees == NULL
    3. Fees IS NULL
    4. Fees = 0
    Marking scheme

    (c) Fees IS NULL

  16. 1 markSQL

    Which data type is most suitable for storing a 10-digit mobile number such as 9876543210?

    1. INT
    2. CHAR(10)
    3. DATE
    4. VARCHAR(2)
    Marking scheme

    (b) CHAR(10)

    The number is never used in calculations, it always has 10 characters, and 9876543210 is larger than the largest INT value (2147483647).

  17. 1 markSQL

    The set of values that an attribute is allowed to take, such as ages 14 to 19 for the column Age, is called the attribute's:

    1. tuple
    2. degree
    3. domain
    4. key
    Marking scheme

    (c) domain

  18. 1 markEmerging Trends

    An online email service used directly in a web browser is an example of which cloud service model?

    1. IaaS
    2. PaaS
    3. SaaS
    4. Grid computing
    Marking scheme

    (c) SaaS

  19. 1 markEmerging Trends

    A smart irrigation system switches on a pump when the soil is dry. The device that measures soil moisture is a:

    1. sensor
    2. router
    3. blockchain
    4. virtual reality headset
    Marking scheme

    (a) sensor

  20. 1 markPython

    Assertion (A): The statement print("5" + 5) produces an error.

    Reason (R): Python does not automatically convert a string into a number when the + operator is used with a string and an integer.

    1. Both A and R are true, and R is the correct explanation of A.
    2. Both A and R are true, but R is not the correct explanation of A.
    3. A is true, but R is false.
    4. A is false, but R is true.
    Marking scheme

    (a) Both A and R are true, and R is the correct explanation of A.

    The statement raises a TypeError because a str cannot be concatenated with an int.

  21. 1 markSQL

    Assertion (A): A table can have more than one candidate key.

    Reason (R): A primary key column can contain NULL values.

    1. Both A and R are true, and R is the correct explanation of A.
    2. Both A and R are true, but R is not the correct explanation of A.
    3. A is true, but R is false.
    4. A is false, but R is true.
    Marking scheme

    (c) A is true, but R is false.

    Any column (or set of columns) that can uniquely identify rows is a candidate key, so there can be several. A primary key can never contain NULL.

Section B

Questions 22 to 28 are very short answer questions carrying 2 marks each. Questions 22 and 26 have an internal choice.

  1. 2 marksComputer System

    Differentiate between system software and application software. Give one example of each.

    Marking scheme
    • System software controls and manages the computer hardware and provides a platform for other programs, e.g. an operating system such as Linux or Windows, or a device driver.
    • Application software is used by people to do a particular task, e.g. a word processor, a spreadsheet or a school fee-management program.

    1 mark for the difference, ½ mark for each correct example.

    OR

    Differentiate between generic (general-purpose) application software and specific-purpose (customised) application software, with one example of each.

    Marking scheme
    • Generic software is made for a large number of users with common needs, e.g. a word processor or a presentation program.
    • Specific-purpose software is designed for the particular needs of one organisation or task, e.g. a hospital's patient-record system or a school's fee-collection program.

    1 mark for the difference, ½ mark for each example.

  2. 2 marksComputer System

    Name the two main parts of the Central Processing Unit (CPU). Write one function of each.

    Marking scheme
    • Arithmetic Logic Unit (ALU): performs arithmetic (addition, subtraction, etc.) and logical (comparison) operations.
    • Control Unit (CU): controls and coordinates all the units of the computer; it fetches instructions and tells the other parts what to do.

    ½ mark for each name and ½ mark for each function. (Registers may also be mentioned as part of the CPU.)

  3. 2 marksComputer System

    Rohan deleted all his files and emptied the Recycle Bin before selling his old laptop. Explain why this may not protect his personal data, and suggest one safe way to remove the data.

    Marking scheme
    • When a file is deleted, the operating system only removes its entry and marks the space as free. The data stays on the disk until it is overwritten, so recovery software can bring it back. (1 mark)
    • Safe way: use a data-wiping (shredding) tool that overwrites the whole disk several times, or format and overwrite the disk; or remove the disk and keep or physically destroy it. (1 mark for any one)
  4. 2 marksPython

    The following code is meant to print "Pass" when the marks are 33 or more and "Fail" otherwise. Rewrite it after removing all the errors and underline each correction.

    Python
    marks = input("Enter marks: ")
    if marks >= 33
        print("Pass")
    else
    print("Fail")
    Marking scheme

    Corrected code (corrections: int() around input(), colon after the if condition, colon after else, indentation of the last print). ½ mark for each of the four corrections.

    Python
    marks = int(input("Enter marks: "))
    if marks >= 33:
        print("Pass")
    else:
        print("Fail")
    Output
    Enter marks: 27
    Fail
  5. 2 marksPython

    Write the output of the following code.

    Python
    L = [5, 10, 15, 20]
    L.append(25)
    L.remove(10)
    L.insert(1, 7)
    print(L)
    print(L.index(15), len(L))
    Marking scheme

    1 mark for each correct line of output.

    Python
    L = [5, 10, 15, 20]
    L.append(25)
    L.remove(10)
    L.insert(1, 7)
    print(L)
    print(L.index(15), len(L))
    Output
    [5, 7, 15, 20, 25]
    2 5
    OR

    Write the output of the following code.

    Python
    stock = {"pen": 40, "pencil": 25}
    stock["eraser"] = 30
    stock["pen"] = stock["pen"] - 15
    for k, v in stock.items():
        print(k, v)
    print(len(stock))
    Marking scheme

    ½ mark for each correct line of output.

    Python
    stock = {"pen": 40, "pencil": 25}
    stock["eraser"] = 30
    stock["pen"] = stock["pen"] - 15
    for k, v in stock.items():
        print(k, v)
    print(len(stock))
    Output
    pen 25
    pencil 25
    eraser 30
    3
  6. 2 marksPython

    Evaluate the following Python expressions and write the result of each, showing the order of evaluation:

    1. 15 - 4 * 3 // 2
    2. not 5 > 3 or 4 < 2 and True
    Marking scheme
    1. 4 * 3 = 12, then 12 // 2 = 6, then 15 - 6 = 9
    2. 5 > 3 is True so not gives False; 4 < 2 and True is False; False or False = False

    1 mark for each correct result with working (½ mark for the result alone). Check with:

    Python
    print(15 - 4 * 3 // 2)
    print(not 5 > 3 or 4 < 2 and True)
    Output
    9
    False
  7. 2 marksSQL

    Classify the following SQL commands as DDL or DML:

    CREATE TABLE, UPDATE, ALTER TABLE, INSERT INTO

    Marking scheme
    • DDL: CREATE TABLE, ALTER TABLE (they define or change the structure)
    • DML: UPDATE, INSERT INTO (they change the data)

    ½ mark for each correct classification.

Section C

Questions 29 to 32 are short answer questions carrying 3 marks each. Questions 29 and 32 have an internal choice.

  1. 3 marksPython

    Write a Python program that accepts the number of electricity units consumed in a month and calculates the bill as follows:

    • first 100 units: Rs 5 per unit
    • next 100 units (101 to 200): Rs 7 per unit
    • above 200 units: Rs 10 per unit
    Marking scheme

    ½ mark for input with int(), 2 marks for the correct if-elif-else slabs, ½ mark for output. Sample run with 260 units: 500 + 700 + 600 = 1800.

    Python
    units = int(input("Enter units consumed: "))
    if units <= 100:
        bill = units * 5
    elif units <= 200:
        bill = 100 * 5 + (units - 100) * 7
    else:
        bill = 100 * 5 + 100 * 7 + (units - 200) * 10
    print("Bill amount: Rs", bill)
    Output
    Enter units consumed: 260
    Bill amount: Rs 1800
    OR

    Write a Python program that accepts a list of integers from the user, creates a new list containing only the even numbers, and displays the new list, the number of even numbers and their sum.

    Marking scheme

    1 mark for creating the list from input, 1 mark for the loop with the even test, 1 mark for the output (list, count, sum).

    Python
    nums = []
    for w in input("Enter numbers: ").split():
        nums.append(int(w))
    even = []
    for x in nums:
        if x % 2 == 0:
            even.append(x)
    print("Even numbers:", even)
    print("Count:", len(even), "Sum:", sum(even))
    Output
    Enter numbers: 12 7 30 45 18 9 4
    Even numbers: [12, 30, 18, 4]
    Count: 4 Sum: 64
  2. 3 marksSQL

    Consider the table EMPLOYEE(EmpID, Aadhaar, Email, Name, Dept), where each employee has a unique EmpID, a unique Aadhaar number and a unique email address. Identify (i) the candidate keys, (ii) a suitable primary key with a reason, and (iii) the alternate keys.

    Marking scheme
    1. Candidate keys: EmpID, Aadhaar and Email (each can uniquely identify a row). (1 mark)
    2. Primary key: EmpID, because it is short, assigned by the organisation and never changes or stays empty. (½ mark key + ½ mark reason)
    3. Alternate keys: Aadhaar and Email, the candidate keys not chosen as the primary key. (1 mark)

    Name and Dept are not keys because two employees can share them.

  3. 3 marksSQL

    Consider the table BOOK given below. Write SQL queries for the following:

    1. Display the title and price of books priced between 300 and 600.
    2. Increase the price of all the books written by Meena Rao by 50.
    3. Display the BookID and Title of the books whose quantity has not been recorded.
    BookIDTitleAuthorPriceQty
    B01The Silent RiverMeena Rao45012
    B02Coding for KidsArun Bhat29930
    B03Stars Above LadakhTsering Dolma620NULL
    B04Monsoon TalesMeena Rao3758
    B05Data Made SimpleKavita Iyer54015
    Marking scheme

    1 mark for each correct query. (Outputs are shown for checking; the UPDATE runs before the third query.)

    MySQL
    SELECT Title, Price FROM BOOK WHERE Price BETWEEN 300 AND 600;
    UPDATE BOOK SET Price = Price + 50 WHERE Author = 'Meena Rao';
    SELECT BookID, Title FROM BOOK WHERE Qty IS NULL;
    Output
    +------------------+-------+
    | Title            | Price |
    +------------------+-------+
    | The Silent River |   450 |
    | Monsoon Tales    |   375 |
    | Data Made Simple |   540 |
    +------------------+-------+
    3 rows in set
    
    Query OK, 2 rows affected
    Rows matched: 2  Changed: 2  Warnings: 0
    
    +--------+--------------------+
    | BookID | Title              |
    +--------+--------------------+
    | B03    | Stars Above Ladakh |
    +--------+--------------------+
    1 row in set
  4. 3 marksEmerging Trends

    What is Big Data? Explain any two of its characteristics with an example.

    Marking scheme

    Big Data is a collection of data so large and complex, and produced so fast, that traditional database tools cannot store and process it easily. (1 mark)

    Any two characteristics (1 mark each):

    • Volume: the huge amount of data, e.g. crores of UPI transactions every day.
    • Velocity: the speed at which data is produced and must be processed, e.g. live data from traffic cameras.
    • Variety: different forms of data such as text, images, video and sensor readings.
    • Veracity: the data may be inaccurate or uncertain, so its quality must be checked.
    • Value: the useful information that can be drawn from the data.
    OR

    Differentiate between Augmented Reality (AR) and Virtual Reality (VR) with one example of each. Also write one use of robotics.

    Marking scheme
    • AR adds computer-generated images or information on top of the real world seen through a camera or glasses, e.g. a mobile app that shows how a sofa will look in your room. (1 mark)
    • VR places the user in a completely computer-generated environment, usually through a headset, e.g. a virtual tour of a historical monument. (1 mark)
    • One use of robotics: robots used in car factories for welding, robots in hospitals for precise surgery, or drones for spraying crops. (1 mark)

Section D

Questions 33 and 34 are case-based questions carrying 4 marks each.

  1. 4 marksPython

    A school canteen stores the prices of its items in a dictionary:

    menu = {"Samosa": 15, "Idli": 25, "Sandwich": 30, "Juice": 20}

    Write Python statements for the following:

    1. Add a new item "Poha" with price 18.
    2. Change the price of Juice to 22.
    3. Print the names of the items that cost more than 20.
    4. Print the total of all prices and the highest price.
    Marking scheme

    1 mark for each part. The parts are shown together and run in order:

    Python
    menu = {"Samosa": 15, "Idli": 25, "Sandwich": 30, "Juice": 20}
    menu["Poha"] = 18                    # 1
    menu["Juice"] = 22                   # 2
    for item in menu:                    # 3
        if menu[item] > 20:
            print(item)
    print(sum(menu.values()), max(menu.values()))   # 4
    Output
    Idli
    Sandwich
    Juice
    110 30
  2. 4 marksSQL

    A clinic keeps the records of its patients in the table PATIENT shown below. PID is the primary key.

    Answer the following:

    1. Write the SQL command to create the table PATIENT with suitable data types.
    2. Display the names of the patients in Cardiology or ENT who are older than 50.
    3. Display the name and fee of the patients admitted in January 2025.
    4. What are the degree and cardinality of the table? What will they be after two more patients are added?
    PIDPNameGenderAgeDeptFeeAdmitDate
    1Ramesh GuptaM62Cardiology8002025-01-14
    2Sunita DasF45ENT5002025-01-20
    3Joseph MathewM71ENT5002025-02-03
    4Pooja SainiF29Orthopaedics6502025-01-28
    5Abdul KarimM55Cardiology8002025-02-11
    6Lalita NegiF58Orthopaedics6502025-01-09
    Marking scheme

    1 mark for each part.

    1. Degree = 7 (columns), cardinality = 6 (rows). After adding two rows the degree stays 7 and the cardinality becomes 8.

    Parts 1 to 3 (the CREATE is shown on a fresh database; the queries run on the data above):

    MySQL
    CREATE TABLE PATIENT (
        PID       INT PRIMARY KEY,
        PName     VARCHAR(25),
        Gender    CHAR(1),
        Age       INT,
        Dept      VARCHAR(15),
        Fee       INT,
        AdmitDate DATE
    );
    SELECT PName FROM PATIENT
    WHERE (Dept = 'Cardiology' OR Dept = 'ENT') AND Age > 50;
    SELECT PName, Fee FROM PATIENT
    WHERE AdmitDate BETWEEN '2025-01-01' AND '2025-01-31';
    Output
    Query OK, 0 rows affected
    
    +---------------+
    | PName         |
    +---------------+
    | Ramesh Gupta  |
    | Joseph Mathew |
    | Abdul Karim   |
    +---------------+
    3 rows in set
    
    +--------------+------+
    | PName        | Fee  |
    +--------------+------+
    | Ramesh Gupta |  800 |
    | Sunita Das   |  500 |
    | Pooja Saini  |  650 |
    | Lalita Negi  |  650 |
    +--------------+------+
    4 rows in set

Section E

Questions 35 to 37 are long answer questions carrying 5 marks each. Question 35 has an internal choice.

  1. 5 marksPython

    Write a Python program that:

    1. accepts n integers from the user and stores them in a list,
    2. displays the sum and the average of the numbers,
    3. counts and displays how many numbers are positive, negative and zero, and
    4. displays the list in descending order.
    Marking scheme

    Marking: creating the list with a loop and input (1½), sum and average (1), counting with if-elif-else (1½), sorting in descending order and display (1).

    Python
    nums = []
    n = int(input("How many numbers? "))
    for i in range(n):
        nums.append(int(input("Enter number: ")))
    
    total = sum(nums)
    print("Sum =", total, " Average =", total / n)
    
    pos = neg = zero = 0
    for x in nums:
        if x > 0:
            pos += 1
        elif x < 0:
            neg += 1
        else:
            zero += 1
    print("Positive:", pos, "Negative:", neg, "Zero:", zero)
    
    nums.sort(reverse=True)
    print("Descending order:", nums)
    Output
    How many numbers? 6
    Enter number: 14
    Enter number: -3
    Enter number: 0
    Enter number: 27
    Enter number: -8
    Enter number: 9
    Sum = 39  Average = 6.5
    Positive: 3 Negative: 2 Zero: 1
    Descending order: [27, 14, 9, 0, -3, -8]
    OR

    Write a Python program that accepts a sentence from the user and displays:

    1. the number of words,
    2. the longest word,
    3. all the words having more than 4 letters, and
    4. the number of uppercase letters in the sentence.
    Marking scheme

    Marking: input and split() (1), number of words (½), longest word with a loop (1½), words with more than 4 letters (1), uppercase count (1).

    Python
    s = input("Enter a sentence: ")
    words = s.split()
    print("Number of words:", len(words))
    
    longest = words[0]
    for w in words:
        if len(w) > len(longest):
            longest = w
    print("Longest word:", longest)
    
    print("Words with more than 4 letters:")
    for w in words:
        if len(w) > 4:
            print(w)
    
    up = 0
    for ch in s:
        if ch.isupper():
            up += 1
    print("Uppercase letters:", up)
    Output
    Enter a sentence: Our School Team won the Zonal Quiz Trophy in Pune
    Number of words: 10
    Longest word: School
    Words with more than 4 letters:
    School
    Zonal
    Trophy
    Uppercase letters: 7
  2. 5 marksSQL

    (a) What is a Database Management System (DBMS)? Write two advantages of using a DBMS over storing data in separate files.

    (b) Write SQL commands to:

    1. create a table EMPLOYEE with the columns EmpID (integer, primary key), Name (up to 20 characters, cannot be empty), Dept (up to 15 characters), Salary (decimal number with 2 places) and DOJ (date of joining);
    2. add a column Email that can store up to 40 characters;
    3. increase the size of the Name column to 30 characters.
    Marking scheme

    (a) A DBMS is software used to create, store, manage and retrieve data in databases, e.g. MySQL. (1 mark)

    Any two advantages (½ mark each): less data redundancy (no repeated copies), data consistency, easy sharing among many users, data security through user permissions, easy searching with queries.

    (b) 1 mark for each correct command. The output of DESC confirms the final structure:

    MySQL
    CREATE TABLE EMPLOYEE (
        EmpID  INT PRIMARY KEY,
        Name   VARCHAR(20) NOT NULL,
        Dept   VARCHAR(15),
        Salary DECIMAL(9,2),
        DOJ    DATE
    );
    ALTER TABLE EMPLOYEE ADD Email VARCHAR(40);
    ALTER TABLE EMPLOYEE MODIFY Name VARCHAR(30) NOT NULL;
    DESC EMPLOYEE;
    Output
    Query OK, 0 rows affected
    
    Query OK, 0 rows affected
    Records: 0  Duplicates: 0  Warnings: 0
    
    Query OK, 0 rows affected
    Records: 0  Duplicates: 0  Warnings: 0
    
    +--------+--------------+------+-----+---------+-------+
    | Field  | Type         | Null | Key | Default | Extra |
    +--------+--------------+------+-----+---------+-------+
    | EmpID  | int          | NO   | PRI | NULL    |       |
    | Name   | varchar(30)  | NO   |     | NULL    |       |
    | Dept   | varchar(15)  | YES  |     | NULL    |       |
    | Salary | decimal(9,2) | YES  |     | NULL    |       |
    | DOJ    | date         | YES  |     | NULL    |       |
    | Email  | varchar(40)  | YES  |     | NULL    |       |
    +--------+--------------+------+-----+---------+-------+
    6 rows in set
  3. 5 marksSQL

    Consider the table TRAVEL given below. Write SQL commands for the following:

    1. Display the passenger name, source and destination of journeys with fare from 500 to 800 (both included).
    2. Display the passenger name and fare of the AC journeys that start from Delhi.
    3. Display the TID and passenger name of the non-AC journeys whose fare has been recorded.
    4. Set the fare of journey 104 to 600.
    5. Delete the journeys made before 1 May 2025.
    TIDPassengerSourceDestinationFareTDateClass
    101Nisha VermaDelhiJaipur7602025-04-12AC
    102Karthik RChennaiMadurai5402025-04-15Sleeper
    103Mohit JainDelhiAgra4102025-05-02AC
    104Sara ThomasKochiChennaiNULL2025-05-09Sleeper
    105Harish PatelAhmedabadMumbai9802025-05-21AC
    106Anjali BoseKolkataPatna6502025-06-01Sleeper
    Marking scheme

    1 mark for each correct command. The commands were run in the order given; outputs are shown for checking.

    MySQL
    SELECT Passenger, Source, Destination FROM TRAVEL
    WHERE Fare BETWEEN 500 AND 800;
    SELECT Passenger, Fare FROM TRAVEL
    WHERE Source = 'Delhi' AND Class = 'AC';
    SELECT TID, Passenger FROM TRAVEL WHERE Fare IS NOT NULL AND Class <> 'AC';
    UPDATE TRAVEL SET Fare = 600 WHERE TID = 104;
    DELETE FROM TRAVEL WHERE TDate < '2025-05-01';
    Output
    +-------------+---------+-------------+
    | Passenger   | Source  | Destination |
    +-------------+---------+-------------+
    | Nisha Verma | Delhi   | Jaipur      |
    | Karthik R   | Chennai | Madurai     |
    | Anjali Bose | Kolkata | Patna       |
    +-------------+---------+-------------+
    3 rows in set
    
    +-------------+------+
    | Passenger   | Fare |
    +-------------+------+
    | Nisha Verma |  760 |
    | Mohit Jain  |  410 |
    +-------------+------+
    2 rows in set
    
    +-----+-------------+
    | TID | Passenger   |
    +-----+-------------+
    | 102 | Karthik R   |
    | 106 | Anjali Bose |
    +-----+-------------+
    2 rows in set
    
    Query OK, 1 row affected
    Rows matched: 1  Changed: 1  Warnings: 0
    
    Query OK, 2 rows affected