CBSE Class 12 Informatics Practices 2022 — Set 90/1/1

Srikanth created the following table STUDENT in his database. Table : STUDENT | RollNo | Name | Class | Marks | | --- | --- | --- | --- | | 1 | Ritika | 12 | 40 | | 2 | Angad | 12 | 35 | | 3 | Kaveri | 11 | 42 | | 4 | Lalitha | 12 | 21 | | 5 | Daniel | 11 | 44 | | 6 | Rabindra | 11 | 39 | | 7 | Rabia | 11 | 28 | He now wants to count number of students in each class where the number of students is more than 3. He has executed the following query : SELECT MAX(Marks) FROM STUDENT WHERE COUNT(*)>3 GROUP BY Class; But, he got an error. Identify the error(s) and rewrite the query. Also underline the correction(s) done.

Ms. Mohini is working in a school and stores the details of all students in a table SCHOOLDATA. TABLE : SCHOOLDATA | Admno | Name | Class | House | Percent | Gender | Dob | | --- | --- | --- | --- | --- | --- | --- | | 20150001 | Aditya Das | 10 | Green | 86 | Male | 2006-02-20 | | 20140212 | Harsh Sharma | 11 | Red | 75 | Male | 2004-10-05 | | 20090234 | Swapnil Pant | 10 | Yellow | 84 | Female | 2005-11-21 | | 20130216 | Soumen Rao | 9 | Red | 91 | Male | 2006-04-10 | | 20190227 | Rahil Arora | 10 | Blue | 70 | Male | 2005-05-14 | | 20120200 | Akasha Singh | 11 | Red | 64 | Female | 2004-12-16 | Write SQL statements from the above given table to : (i) To remove leading spaces from the column Name. (ii) Display the names of students who were born on Sunday. OR Predict the output of the following SQL queries from the given table : SCHOOLDATA (i) SELECT MAX(Percent) FROM SCHOOLDATA; (ii) SELECT LEFT(Gender,1),Name FROM SCHOOLDATA WHERE YEAR(Dob)=2005;

Predict the output of the following SQL queries : (i) SELECT TRIM(“ ALL THE BEST ”) ; (ii) SELECT POWER(5,2); (iii) SELECT UPPER(MID(“start up india”,10)); OR Consider a table “MYPET” with the following data : Table : MYPET | Petᵢd | PetName | Breed | LifeSpan | Price | Discount | | --- | --- | --- | --- | --- | --- | | 101 | Rocky | Labrador Retriever | 12 | 16000 | 5 | | 202 | Duke | German Shepherd | 13 | 22000 | 10 | | 303 | Oliver | Bulldog | 10 | 18000 | 7 | | 404 | Cooper | Yorkshire Terrier | 16 | 20000 | 12 | | 505 | Oscar | Shih Tzu | NULL | 25000 | 8 | Write SQL queries for the following : (i) Display the Breed of all the pets in uppercase. (ii) Display the total price of all the pets. (iii) Display the average life span of all the pets.

Write the names of SQL functions to perform the following operations : (i) Display name of the Month from your date of birth. (ii) Convert email-id to lowercase. (iii) Count the number of characters in your name.

Consider the following table : PRODUCT Table : PRODUCT | PID | PNAME | PRICE | QUANTITY | | --- | --- | --- | --- | | P1001 | Eraser | 10.50 | 5 | | P1002 | Ball Pen | 15.00 | 2 | | P1003 | Gel Pen | 25.10 | 3 | | P1004 | Ruler | 5.00 | 1 | Find the output of the following SQL queries : (i) SELECT 10+MOD(QUANTITY,3) FROM PRODUCT WHERE PNAME = “Eraser”; (ii) SELECT ROUND(PRICE,2)*QUANTITY FROM PRODUCT WHERE QUANTITY > 2; (iii) SELECT UCASE(RIGHT(PNAME,2)) FROM PRODUCT;

Consider the table : ITEM Table : ITEM | SNo | Itemname | Type | Price | Stockdate | | --- | --- | --- | --- | --- | | 1 | Chaises | Living | 11500.58 | 2020-02-19 | | 2 | Accent Chairs | Living | 31000.67 | 2021-02-15 | | 3 | Baker Racks | Kitchen | 25000.623 | 2019-01-01 | | 4 | Sofa | Living | 7000.3 | 2020-10-18 | | 5 | Nightstand | Bedroom | NULL | 2021-07-23 | Write SQL queries for the following : (i) Display all the records in descending order of Stockdate. (ii) Display the Type and total number of items of each Type. (iii) Display the least Price. (iv) Display the Itemname with their price rounded to 1 decimal place.

Consider the following table : Table : SALESMAN | Scode | Sname | Area | Qtysold | Dateofjoin | | --- | --- | --- | --- | --- | | S001 | Ravi | North | 120 | 2015-10-01 | | S002 | Sandeep | South | 105 | 2012-08-01 | | S003 | Sunil | NULL | 68 | 2018-02-01 | | S004 | Subh | West | 280 | 2010-04-01 | | S005 | Ankit | East | 90 | 2018-10-01 | | S006 | Raman | North | NULL | 2019-12-01 | Predict the output for the following SQL queries : (i) SELECT MAX(Qtysold), MIN(Qtysold) FROM SALESMAN; (ii) SELECT COUNT (Area) FROM SALESMAN; (iii) SELECT LENGTH (Sname) FROM SALESMAN WHERE MONTH(Dateofjoin)=10; (iv) SELECT Sname FROM SALESMAN WHERE RIGHT(Scode,1)=5; OR Based on the given table SALESMAN write SQL queries to perform the following operations : (i) Count the total number of salesman. (ii) Display the maximum qtysold from each area. (iii) Display the average qtysold from each area where number of salesman is more than 1. (iv) Display all the records in ascending order of area.

ABC International School, Delhi has different wings Administrative Wing (W1), Primary Wing (W2), Middle Wing(W3) and Secondary Wing(W4) as shown in the diagram : [Diagram: layout of four wings — ADMINISTRATIVE WING (W1), PRIMARY WING (W2), MIDDLE WING (W3), SECONDARY WING (W4) — within the Delhi campus, plus a separate MUMBAI BRANCH block.] The school also has a branch in Mumbai. The school management wants to connect all the wings as well as all the computers of each wing (W1, W2, W3, W4). Distance between the wings are as follows : | | | | --- | --- | | W3 to W1 | 85 m | | W1 to W2 | 40 m | | W2 to W4 | 25 m | | W4 to W3 | 120 m | | W3 to W2 | 150 m | | W1 to W4 | 170 m | Number of computers in each of the wing : | | | | --- | --- | | W1 | 125 | | W2 | 40 | | W3 | 42 | | W4 | 60 | Based on the above specifications, answer the following questions : (i) Suggest the topology and draw the most suitable cable layout for connecting all the wings of Delhi branch. (ii) Suggest the kind of network required (out of LAN, MAN, WAN) for connecting (a) Administrative Wing (W1) with Middle Wing (W3) (b) Administrative Wing (W1) with the Mumbai branch. (iii) Suggest the placement of the following devices with justification : (a) Repeater (b) Switch/Hub (iv) Due to pandemic school had to adopt Online classes. Suggest the protocol that is used for sending the voice signals over internet. Also, give an example of an application of WWW that helped the teachers to send messages instantly to the students.