CBSE Class 11 Computer Science Data Management Worksheet Set E

WS 9 – Data Management

1. What is a database system? What is its need?

2. What is SQL? What are different categories of commands available in SQL?

3. Differentiate between DDL and DML commands.

4. Write two usage of DESC in SQL.

5. Write SQL queries for (i) to (iv) and find outputs for SQL queries (v) to (viii), which are based on the tables:

(i) To display all details from table MEMBER in descending order of ISSUEDATE.
(ii) To display the CODE and BNAME of all Fiction Type books from the table BOOK.
(iii) To display the TYPE and number of books in each TYPE from the table BOOK.
(iv) To display all MNAME and ISSUEDATE of those members from table MEMBER who have books issued (i.e ISSUEDATE) in the year 2017.
(v) SELECT MAX(ISSUEDATE) FROM MEMBER;
(vi) SELECT DISTINCT TYPE FROM BOOK;
(vii) SELECT A.CODE, BNAME, MNO, MNAME FROM BOOK A, MEMBER B WHERE A.CODE=B.CODE ;
(viii) SELECT BNAME FROM BOOK WHERE TYPE NOT IN ("Fiction", "Comic");

6. Create table Employee with the following structure:

Ensure the following specification in created table: ID should be declared as Primary Key, User_ID shold be unique,Salary Must be greater than 5000 , First_Name and Lst_Name must not remain Blank

Write SQL queries for the following :

i. Show the structure of the table Employee.
ii. Insert 3 records in the table Employee.
iii. Modify the SALARY and increase by 1000, for all who get salary less than 6000
iv. For record with ID 4 update record with LAST_NAME as Sharma, USER_ID as E1004 and SALARY as 7800.
v. Add a new coloumn PHONE of type varcahr(12)
vi. Delete the EMPLOYEE record having FIRST_NAME as Manish
vii. Remove Employee Table permanently
viii. Count the total records in the table EMPLOYEE

7. What is foreign key? How do you define a foreign key in your table?

8. Explain the DELETE command in SQL with syntax and example.

9. Observe the following table and answer the parts (i) and (ii) :

(i) In the above table, can we have Qty as primary key.[Answer as yes/no]. Justify your answer.
(ii) If you have to add a column email and phone, name the data types required for it.

10. Define Cardinality and degree of table what is the Degree and Cardinality of the following table.

Please click on below link to download CBSE Class 11 Computer Science Data Management Worksheet Set E