Question 1

Question 1Assertion (A): Database management system is an application software which arranges data in a well-organized manner in the form of tables.Reasoning (R): DBMS acts as an interface between the database stored in the computer memory and the user.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

Both A and R are true and R is the correct explanation of A.ExplanationDatabase Management System (DBMS) is an application software that acts as an interface between the database stored in the computer memory and the user. It enables users to interact with the database and store data in a well-organized manner in the form of tables. The purpose of the DBMS software is to allow the user to create, access, modify, and control a database.

Question 2

Question 2Assertion (A): A database consists of multiple tables.Reasoning (R): A foreign key is used to represent the relationship between two tables.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

Both A and R are true and R is the correct explanation of A.ExplanationIn a database system, data is organized into multiple tables for better organization, management, and query efficiency. A foreign key is a non-key attribute whose value is derived from the primary key of another table in a database. It references the primary key in another table, thereby establishing a relationship between the two tables.

Question 3

Question 3Assertion (A): The limitations of traditional file system are overcome by storing data in a database.Reasoning (R): We can organize related data logically in a database.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

Both A and R are true and R is the correct explanation of A.ExplanationTraditional file systems have limitations such as data redundancy, inconsistency, and difficulties in data sharing and security. In contrast, databases store data in a structured and organized manner, which helps overcome these limitations. They allow us to logically organize related data, making data management, retrieval, and manipulation more efficient.

Question 4

Question 4Assertion (A): The number of attributes in a relation is called the degree of the relation.Reasoning (R): The number of tuples in a relation is called the cardinality of the relation.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

Both A and R are true but R is not the correct explanation of A.ExplanationThe degree of a relation and the cardinality of a relation are two separate concepts in database management. The number of attributes or columns in a relation is called the degree of the relation, while the number of tuples or records in a relation is called the cardinality of the relation.

Question 5

Question 5Assertion (A): Each table must have one primary key.Reasoning (R): Primary key is a set of one or more attributes that uniquely identifies a tuple in a relation.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

Both A and R are true and R is the correct explanation of A.ExplanationIn a database, each table can have only one primary key, which is unique and non-redundant in nature. The primary key is a set of one or more attributes or fields that uniquely identify a tuple or row in a relation.

Question 6

Question 6Assertion (A): A database can have only one table.Reasoning (R): If a piece of data is stored in two places in a database, then it leads to wastage of storage space.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is false but R is true.ExplanationA database can have multiple tables. Data redundancy, which occurs when the same data is repeated in multiple places within a database, leads to wastage of storage space. A DBMS eliminates data redundancy by integrating files, ensuring that multiple copies of the same data are not stored.

Question 7

Question 7Assertion (A): A database constraint can be added or removed any time in/from the database tables.Reasoning (R): Alter table command is used to change the structure of the table.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

Both A and R are true but R is not the correct explanation of A.ExplanationA database constraint can be added or removed from database tables using the ALTER TABLE command, even after the table has already been created. This command is used to modify the structure of a table by altering the definition of its columns.

Question 8

Question 8Assertion (A): SQL has efficient mechanisms to retrieve data stored in multiple tables in a MySQL database.Reasoning (R): The SQL statement CREATE is used to retrieve data from the tables in a database and is also called query statement.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is true but R is false.ExplanationSQL provides efficient mechanisms, such as JOIN operations, to retrieve data from multiple tables in a MySQL database. The SQL statement CREATE is used to create new database objects such as tables, indexes, or views. The SELECT statement is used to retrieve data from tables in a database and is known as a query statement.

Question 9

Question 9Assertion (A): The SQL keyword Like is used with wildcards only.Reasoning (R): '_' underscore and "%" per cent are the two wildcard characters used with LIKE clause.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

Both A and R are true and R is the correct explanation of A.ExplanationThe SQL LIKE keyword allows the use of wildcard characters to perform pattern matching. SQL provides two wildcard characters to use with the LIKE operator: the percent sign (%) which matches any string, and the underscore ("_") which matches any single character.

Question 10

Question 10Assertion (A): DISTINCT clause must be used in an SQL statement to eliminate duplicate rows.Reasoning (R): DISTINCT only works with numeric data type only.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is true but R is false.ExplanationThe DISTINCT clause is used to remove duplicate rows from the results of a SELECT statement. It retrieves only unique values for a column in the table. The DISTINCT keyword in SQL can be used with any data type.

Question 11

Question 11Assertion (A): FLOAT and DOUBLE are data types.Reasoning (R): Both can hold any number up to 23 digits.Both A and R are true and R is the correct explanation of A.Both A and R are true but R is not the correct explanation of A.A is true but R is false.A is false but R is true.

Accepted Answer

A is true but R is false.ExplanationFLOAT and DOUBLE are data types in SQL, used to store decimal numbers. FLOAT can store values with a precision of around 6-7 digits, while DOUBLE can store values with a precision of around 15-16 digits.

Question 12

Question 1Kunal has entered the following SQL command in the table 'STUDENT' that has TotalMarks as one of the columns:SELECT * FROM Student;                         #Statement-1The total number of rows displayed is 20.Then Kunal enters the following command:SELECT * FROM STUDENT WHERE TotalMarks < 100;  #Statement-2 The number of rows displayed is 15.Kunal then enters the following command:SELECT * FROM STUDENT WHERE TotalMarks >= 100; #Statement-3He predicts the output of the above query as 5. Do you agree with Kunal? Give reasons for your answer.

Accepted Answer

I disagree with Kunal's prediction. Since Statement-1 returns all the rows and columns of the table Student i.e., 20, and Statement-2 returns 15 rows with TotalMarks less than 100, it means 20 - 15 = 5 students have TotalMarks greater than 100. However, Statement-3 returns rows where TotalMarks is greater than or equal to 100, which includes students who scored exactly 100, and we don't know how many students scored exactly 100, so the number of rows returned by Statement-3 will be greater than or equal to 5, but not necessarily exactly 5.

Question 13

Question 2(a)Mr. Shivaya is using a table 'COURSE' with the following columns: COURSE_ID, COURSE_NAME. He needs to display the names of all the courses which end with "SCIENCE". He has written the query mentioned below, which is not giving the desired result.SELECT COURSE_ID, COURSE_NAME FROM COURSE WHERE COURSE_NAME = '_SCIENCE';Help Mr. Shivaya to write the correct query.

Accepted Answer

SELECT COURSE_ID, COURSE_NAME FROM COURSE WHERE COURSE_NAME LIKE '%SCIENCE';ExplanationThe "=" operator is used for exact matching and the "_" wildcard character in SQL is used to match a single character, not a sequence of characters. To achieve the desired result, Mr. Shivaya should use the LIKE operator with the "%" wildcard character, which matches any sequence of characters.

Question 14

Question 2(b)Ms. Manisha, a veterinarian, created a table 'VETERINARY' with the following columns:ANIMAL_ID, VACCINATION_DATE, ANIMAL, OWNER_NAME
She wants to see the details of all the animals other than Dog and Cat which she has vaccinated.She has written the following query:SELECT * FROM VETERINARY WHERE ANIMAL NOT IN ('DOG', 'CAT');Write a suitable alternate query for producing the same result.

Accepted Answer

SELECT * FROM VETERINARY 
WHERE ANIMAL != 'DOG' AND ANIMAL != 'CAT';

Question 15

Question 3Your school management has decided to organize cricket matches between students of Classes XI and XII. All the students are divided into four teams—Team Rockstars, Team BigGamers, Team Magnet and Team Current. During the summer vacations, various matches are to be held between these teams. Help your sports teacher do the following:(a) Create a database "Sports" and open it for creating table.(b) Create a table "Team" with the following considerations:It should have a column TeamID for storing an integer value between 1 and 9, which refers to unique identification of a team.Each TeamID should have its associated name (TeamName), which should be a string of length not less than 10 characters.Give the statement to make TeamID the primary key.(c) Show the structure of the table Team using SQL command.(d) As per the preferences of the students, four teams were formed as given below.Insert these four rows in Team table:Row 1: (1, Team Rockstars)Row 2: (2, Team BigGamers)Row 3: (3, Team Magnet)Row 4: (4, Team Current)(e) Display the table Team.

Accepted Answer

Question 16

Question 1A Database is an organized collection of records.

Accepted Answer