MDU wuestion paper (DBMS) 4th sem

B.E. 4th semester (I.T.) Examination, MAY-2009
DATABASE MANAGEMENT SYSTEM
paper-cse-202-E

NOTE: Attempt any five question.

1 (a) What are data model ? Why are they required ? What are the differences between conceptual model and record based models?

(b) Discuss three views of data. What are the difference between logical and physical data independence ?


2 (a) What various symbol used in drawing an ER diagram ? Write significance of each symbol.

(b) Construct an ER diagram for a car-insurance company that has a set of customers, each of whom owns one or more cars. Each car has associated with it zero to any number of recorded accidents.

3 (a) Write about various hashing techniques.

(b) What are direct file ? Differentiate between primary and secondary index.


4 consider the relational database as follows:
Employee(emp name, street, city)
Works (emp name, company name, salary)
Company (company name, city)
Manager (employee name, manager name)
For the following queries, give an expression in relational algebra and tuple relational calculus :

(a) Find the name of all employees who work for first bank corporation.

(b) Find the names, street address and cities of residence of all employee who work for first bank corporation and earn more than Rs, 10,000 per annum.

(c) Find the name of all employees who live in the same city and on the same street as do their managers.

(d) Find the name of all employees who don't work for first bank corporation.

(e) Find the names of all employees who earn more than every employee of small bank corporation.


5 (a) Consider a relation R with five attributes ABCDE. You are given the following dependencies:
A->B, BC->E and ED->A
(1) List all key for R ?
(11) Is R in 3NF ?
(111) IS R in BCNF ?

(b) What are MVDS ? Define 4NF.


6 (a) Differentiate between network model and hierarchical model.

(b) What is meant by database recovery ? How log files are used for it?


7 (a) Write a detailed note on data mining.

(b) What are B-trees ? How and where can they be used ? Discuss their organization.


8 Write short note on :
(a) Distributed databases

(b) parallel databases

(c) SQL

(d) Mapping constraints.