Computer Science: CUET Mock Test - 3 - CUET MCQ

The correct answer is Option 1

Select * from Customer

Where Gender = "M" and Membership >10;

Key Points

SELECT * FROM Customer WHERE Gender = 'M' AND Membership > 10;

• SELECT *: This retrieves all columns from the Customer table. You can replace * with specific column names if you only need certain details.
• FROM Customer: This specifies the table from which data will be retrieved.
• WHERE Gender = 'M': This filters the results to include only customers whose Gender is 'M' (male).
• AND Membership > 10: This further filters the results to include only male customers whose Membership value is greater than 10 months.
• This query effectively combines the conditions for male gender and membership duration to provide the desired output.

The correct answer is Option 3

1. Purpose: Counts customers (count(*)) grouped by each trainer (TId).

2. Correctness:

   • Uses GROUP BY TId to aggregate customers per trainer.

   • count(*) counts all rows (customers) for each TId.

3. Why Not Others?

   • A: Invalid - References Trainer.TId without joining the Trainer table.

   • B: Invalid - Groups by TId but selects TName (not in GROUP BY).

   • D: Invalid - Same as A (references Trainer table without a join).

The correct answer is Option 2

Select TName, Dt_Appoint from Trainer
Where Activity = "Core"
Order by Dt_Appoint desc;

Key PointsThe correct SQL syntax for filtering the records before sorting them is to use the WHERE clause before the ORDER BY clause. Therefore, the query that correctly applies this structure to display the names of all trainers (trainees in the question seems to be a typo since the details pertain to trainers) with their date of appointment in descending order, who are taking core activity, would need to follow this logic.

Among the options given, the correct choice would be the one that places the WHERE clause directly after specifying the table, and before the ORDER BY clause, with the correct syntax for ordering the results in descending order:

Select TName, Dt_Appoint from Trainer Where
Activity = "Core"
Order by Dt_Appoint desc;

The correct answer is Option 1

Update Customer
Set Membership = 12
Where TId = "G101" or TId = "G102";

Key PointsThe correct SQL query to update the membership of all customers, under trainers with code G101 and G102, to 12 months is the one that uses the UPDATE statement to modify the value of the Membership field for all customers that meet the specified condition (their trainer ID being G101 or G102).

• The SET clause is used to specify the new value for the field you want to update.
• The WHERE clause is used to filter the records you want to update.
• When checking for multiple conditions, OR is used to update records that meet either one of the conditions.

Among the options given:
Update Customer
Set Membership = 12
Where TId = "G101" or TId = "G102";

This option correctly:

• Uses the UPDATE statement to indicate that you're going to change some rows in the Customer table.
• Uses Set Membership = 12 to set the Membership field to 12 months for all rows that match the condition.
• Uses the WHERE clause with an OR operator to specify that the condition matches customers whose TId is either "G101" or "G102".

So, the correct answer is:

Update Customer
Set Membership = 12
Where TId = "G101" or TId = "G102";

The correct answer is A, B and E only

Key Points

• Proper joining condition between the Trainer and Customer tables (either implicitly through the WHERE clause or using explicit JOIN syntax which isn't shown here).
• Correct filtering of Trainer salaries within the range of 20000 to 25000.
• Correct aliasing and referencing of column names, especially for the JOIN condition and selected columns.
• Select TName, Salary, Cust_Name, Fee: This selects the desired columns from both tables: TName and Salary from Trainer and Cust_Name (assuming a typo and it should be Cust_Name) and Fee from Customer.
• From Customer, Trainer: This specifies the tables involved in the join.
• Where C.TId = T.TId: This establishes the join condition between the Customer and Trainer tables, ensuring we retrieve data for trainers with matching IDs in both tables.
• and Salary between 20000 and 25000: This filters the results to include only trainers whose salaries fall within the specified range (20000 to 25000).

Options A, B, and E all construct the correct SQL query to display the desired report with proper table joins, column selection, and filtering based on trainer salary.

The correct answer is Full outer join

Key PointsA "Full Outer Join" (also known as Full Join) is used in SQL to combine rows from two or more tables based on a related column. The outcome of a Full Outer Join includes all the records from both the left and the right tables, and it matches rows from both tables where the join condition is met. If there isn't a match, the result is NULL on either the left or the right side (or both, in case of no common relation).

So the correct answer is Full outer join

Additional Information

• A NATURAL JOIN is a type of join operation in SQL that is used to combine rows from two or more tables based on the columns they have in common. This can be particularly useful when you have two tables that contain related data, but do not have an explicitly defined foreign key relationship.
• Unlike other join types, NATURAL JOIN doesn't require a specific condition to match columns from one table with another, as it automatically matches columns with the same name in both tables. For example, if both tables have a column named 'customer_id', the NATURAL JOIN will use this column as the join condition.
• 

The correct answer is 16

Key PointsIn the context of relational databases and SQL, a Cartesian product (or CROSS JOIN) refers to a JOIN operation that returns the combination of every row of the first table with every row of the second table.
If table1 has n rows and table2 has m rows, the Cartesian product of these two tables will result in a table with n*m rows.
If table1 has 4 rows and table2 has 4 rows, the Cartesian product of these two tables will result in a table with 4*4 = 16 rows.
So the correct answer is 16

The correct answer is 4

Key PointsA "Left Outer Join" is another type of JOIN operation in SQL, which is used to combine rows from two or more tables based on a related column between them.

Unlike the Right Outer Join, the Left Outer Join returns all the records from the left table, and the matched records from the right table. If there is no match found in the right table, the result is NULL on the right-side part.

Here the above table is left outer join they have contain four row so correct answer is 4.

The correct answer is 4

Key Points A "Right Outer Join" is a concept from SQL (Structured Query Language), used in relational databases. It's a method of combining two tables based on a common column between them, showing all records from the 'right' table and matched records from the 'left' table.

The result of a right outer join contains all the records from the right table and any records in the left table that match the join condition. For the records in the right table that do not have a corresponding match in the left table, the result is NULL in the columns of the left table.

Here the above table is right outer join they have contain four row so correct answer is 4.

The correct answer is Option 2

Key PointsA "Right Outer Join" is a concept from SQL (Structured Query Language), used in relational databases. It's a method of combining two tables based on a common column between them, showing all records from the 'right' table and matched records from the 'left' table.

The result of a right outer join contains all the records from the right table and any records in the left table that match the join condition. For the records in the right table that do not have a corresponding match in the left table, the result is NULL in the columns of the left table.

When we are allocating the memory using new operator and allocation fail, then bad_alloc exception is thrown by the program.

A file management system is designed to handle and access multiple files simultaneously. This capability allows users or applications to work with several files at once, performing operations like reading, writing, or modifying data across different files as needed.

The PRIMARY KEY constraint uniquely identifies each record in a table. Primary keys must contain UNIQUE values, and cannot contain NULL values.

'Try' is used to define the code block where an exception might occur. 'Raise' is used to trigger a specific exception intentionally. 'Finally' defines the code block that will execute regardless of whether an exception occurs. 'Except' is used to handle the raised exception.

We can do all the above using computer networks.

The 'x' file access mode is used to open a file for exclusive creation. This mode allows you to create a new file but will raise an error if the file already exists. This mode is useful when you want to create a new file and ensure that it does not already exist. The 'a' file access mode is used to open a file for appending data to the end of the file. This mode allows you to write to the file but not overwrite any existing content. If the file does not exist, it will be created.

When stack is completely full (i.e. TOP= MaxSize -1) and we try to insert more elements onto stack then this condition is called overflow condition and no further element could be inserted now until any element is deleted.

Both the stack and queue are the linear data structure, which means that the elements are stored sequentially and accessed in a single run.

• (A) Primary Data → (II) Data collected directly from first-hand sources, such as through surveys, interviews, or experiments.
• (B) Secondary Data → (III) Data obtained from existing sources, including books, articles, or official records.
• (C) Data Collection → (IV) The process of gathering data using techniques like observations, surveys, or experiments.
• (D) Data Organization → (I) Arranging raw data into tables, charts, or graphs to facilitate analysis and interpretation.

The major limitation of binary search is that there is a need for the sorted array to perform the binary search operation. If the array is not sorted the output is either not correct or maybe after a long number of steps and according to the data structure, the output should come in a minimum number of steps.
Not a limitation of Binary search :Binary search algorithm is not efficient when the data elements are more than 1000.

Data processing refers to the process of performing specific operations on a set of data or a database.
Process data is called information.

In Python, a queue can be implemented using a list. The append() method adds an element (e.g., a, the student name) to the end of the list, simulating enqueue in a FIFO queue. Thus, queue.append(a) is correct. Answer: A.

The del keyword is used to delete objects. In Python, everything is an object. So, the del keyword can also be used to delete variables, lists, or parts of a list, etc.

The len() function returns the number of items (length) in an object.

isEmpty(q) would be a valid function if it's defined somewhere else in the code, but in Python, you typically use the built-in check if not queue to check for an empty list (queue). However, since the question asks for filling Statement-2, the intended method seems to be isEmpty(q)

In Python, the typical way to check if a list is empty is using if not queue

The correct option is 21 and 20
CONCEPT:
File Transfer Protocol (FTP) is a standard application layer communication protocol used for the transfer of files or data from a server to a client on a computer network.
FTP is built on a client-server architecture that runs on top of TCP just like HTTP and uses separate control and data connections between the client and the server.
FTP uses two port numbers 20 and 21. Port 21 is used for the establishment of a connection between the 2 computers and port 20 is used to transfer data.
Port 20- Data 
Port 21- Communication

Concept:
Adware:
Adware is software that displays unwanted and aggressive advertising to end-users (for example, pop-up adverts). Malvertising is the use of legal advertisements to distribute malware to end-user PCs.
Adware earns cash for its creator by showing internet adverts in the software's user interface or on a screen that appears in the user's face during the installation process.
Hence the correct answer is adware.

• The internet is a globally connected network system that transmits data via various types of media; Sometimes it is referred to as a ‘network of networks’
• The internet is a network of global exchanges including private, public, business, academic and government networks connected by guided, wireless and fibre-optic technologies
• A server is a computer program or a device that provides functionality for other programs or devices, called "clients"
• A client is a computer that connects to and uses the resources of a remote computer, or server
• A component is a software object, intended to interact with other components
• Layered architecture is a type of client-server architecture in which functions are physically separated

Computer networks constituting the internet are connected by telephones, underwater cables, and Satellites.

• A computer network, also known asa data network, is a telecommunications network which allows computers to exchange its data.
• The Internet has emerged as a useful means of global communication, services and information sharing.
• A huge network of millions of computer networks constitutes the Internet. These networks are connected by telephones, underwater cables, and satellites.