Database Management System 2078

Section A
Long Answer Questions
Attempt any TWO questions. [2 × 10 = 20]

1. What is an E-R Diagram? Explain various symbols used in the E-R Diagram. [3+7]

2. What is Transaction? State and explain the properties of Transaction. [2+8]

3. From the relation given below, answer the following questions.
EMPLOYEE (Ssn, Fname, Mnit, Name, Bdate, Address, Sex, Salary, Super_ssn, Dno)
DEPARTMENT (Dname, Dnumber, Mgr_ssn, Mgr_start_date)
PROJECT (Pname, Pnumber, Plocation, Dnum)
DEPENDENT (Essn, Dependent_name, Sex, Bdate, Relationship)
DEPT_LOCATIONS (Dnumber, Dlocation)
(a) Retrieve all the attributes of employees who work for the 'Computer' department (department no 5) using SQL.
(b) For each Department, retrieve the department number, the number of employees in department, and their average salary using SQL.
(c) For each project on which more than two employees work, retrieve the project number, name, and the number of employees who work on that project using SQL.
(d) Select the EMPLOYEE tuples whose department is 10, or those whose salary is greater than Rs 50,000 using Relational Algebra.
(e) Retrieve the names of employees who have no dependents using Relational Algebra. [5 × 2]

Section B
Short Answer Questions
Attempt any EIGHT questions. [8 × 5 = 40]

4. What are different types of Database Users? Explain in Brief. [5]

5. What is Primary key and Foreign Key? Why is this required in the DBMS? [5]

6. What is Integrity constraint? What are the three main categories of Integrity constraints. [2+3]

7. What is Functional Dependency? Explain 3NF with Examples. [5]

8. What is Schedule? Explain Serializability and Conflict Schedule. [2+2+1]

9. What is starvation in DBMS? Explain with example. [5]

10. During ER-to-Relational Mapping, explain with example to map 1:N and N:M relationship into a relation. [5]

11. What is NoSQL? What are the types of NoSQL? Explain. [5]

12. Explain Data Models, Schemas, and Instances. [5]