Arts (English Medium) कक्षा १२ - CBSE Question Bank Solutions for Computer Science (Python)

Identify the type of data being collected/generated in the following scenario:

Writing tweets

Identify the type of data being collected/generated in the following scenario:

Filling out an application form online.

For the annual day celebrations, the teacher is looking for an anchor in a class of 42 students. The teacher would make a selection of an anchor on the basis of singing skills, writing skills, as well as monitoring skills.

Which mode of data collection should be used?

Give the term for the following:

DBMS creates a file that contains a description of the data stored in the database.

Differentiate between Database state and database schema.

Differentiate between the following statement:

ALTER and UPDATE

A shop called Wonderful Garments which sells school uniforms maintains a database SCHOOLUNIFORM as shown below. It consisted of two relations - UNIFORM and COST. They made UniformCode the primary key for UNIFORM relations. Further, they used UniformCode and Size to be composite keys for COSTrelation. By analyzing the database schema and database state, specify SQL queries to rectify the following anomalies.

1. M/S Wonderful Garments also keeps handkerchiefs of red colour, medium size of Rs. 100 each.
2. INSERT INTO COST (UCode, Size, Price) values (7, 'M', 100);
   When the above query is used to insert data, the values for the handkerchief without entering its details in the UNIFORM relation are entered. Make a provision so that the data can be entered in the COST table only if it is already there in the UNIFORM table.
3. Further, they should be able to assign a new UCode to an item only if it has a valid UName. Write a query to add appropriate constraints to the SCHOOLUNIFORM database.
4. Add the constraint so that the price of an item is always greater than zero.

Suppose your school management has decided to conduct cricket matches between students of Class XI and Class XII. Students of each class are asked to join any one of the four teams – Team Titan, Team Rockers, Team Magnet, and Team Hurricane. During summer vacations, various matches will be conducted between these teams. Help your sports teacher to do the following:

1. Create a database “Sports”.
2. Create a table “TEAM” with the following considerations:
   i) It should have a column TeamID for storing an integer value between 1 to 9, which refers to the unique identification of a team.
   ii) Each TeamID should have its associated name (TeamName), which should be a string of length not less than 10 characters.
3. Using table level constraint, make TeamID the primary key.
4. Show the structure of the table TEAM using a SQL statement.
5. As per the preferences of the students four teams were formed as given below. Insert these four rows in the TEAM table:
   Row 1: (1, Team Titan)
   Row 2: (2, Team Rockers)
   Row 3: (3, Team Magnet)
   Row 3: (4, Team Hurricane)
6. Show the contents of the table TEAM using a DML statement.
7. Now create another table MATCH_DETAILS and insert data as shown below. Choose appropriate data types and constraints for each attribute.

Using the CARSHOWROOM database given in the chapter, write the SQL queries for the following:

1. Add a new column Discount in the INVENTORY table.
2. Set appropriate discount values for all cars keeping in mind the following:
   (i) No discount is available on the LXI model.
   (ii) VXI model gives a 10 percent discount.
   (iii) A 12 percent discount is given on cars other than the LXI model and VXI model.
3. Display the name of the costliest car with the fuel type “Petrol”.
4. Calculate the average discount and total discount available on Baleno cars.
5. List the total number of cars having no discount.

Mention any two main advantages of using a network of computing devices.

Write down the names of a few commonly used networking devices.

How is tree topology different from bus topology?

What do you mean by a modem? Why is it used?

Explain the following device:

Switch

Explain the following device:

Repeater

Explain the following device:

Gateway

Explain the following device:

Router

Explain the following device:

NIC

Which communication mode allows communication in both directions simultaneously?

______ command is used to remove the primary key from a table in SQL.