Code: DC-10 Subject: DATABASE MANAGEMENT SYSTEMS

Time: 3 Hours Max. Marks: 100

 

NOTE: There are 11 Questions in all.

 

      Question 1 is compulsory and carries 16 marks. Answer to Q. 1. must be written in the space provided for it in the answer book supplied and nowhere else.

      Answer any THREE Questions each from Part I and Part II. Each of these questions carries 14 marks.

      Any required data not explicitly given, may be suitably assumed and stated.

 

 

Q.1 Choose the correct or best alternative in the following: (2x8)

a.       The property / properties of a database is / are :

(A) It is an integrated collection of logically related records.

(B) It consolidates separate files into a common pool of data records.

(C)    Data stored in a database is independent of the application programs using it.

(D)    All of the above.

 

b.      The DBMS language component which can be embedded in a program is

(A) The data definition language (DDL).

(B) The data manipulation language (DML).

(C) The database administrator (DBA).

(D) A query language.

 

c. A relational database developer refers to a record as

 

(A) a criteria. (B) a relation.

(C) a tuple. (D) an attribute.

 

d. The relational model feature is that there

 

(A)     is no need for primary key data.

(B)     is much more data independence than some other database models.

(C)     are explicit relationships among records.

(D)    are tables with many dimensions.

 

e. Conceptual design

(A)     is a documentation technique.

(B)     needs data volume and processing frequencies to determine the size of the database.

(C)     involves modelling independent of the DBMS.

(D)    is designing the relational model.

 

f. The method in which records are physically stored in a specified order according to a key field in each record is

 

(A) hash. (B) direct.

(C) sequential. (D) all of the above.

 

g. A subschema expresses

(A) the logical view. (B) the physical view.

(C) the external view. (D) all of the above.

h. Count function in SQL returns the number of

 

(A) values. (B) distinct values.

(C) groups. (D) columns.

 

PART I

Answer any THREE Questions. Each question carries 14 marks.

 

Q.2 a. Discuss the main advantages of using a DBMS. (7)

 

b. What are the different types of database end users? Discuss the main activities of each. (7)

Q.3 a. Describe the three-schema architecture. (7)

b. Discuss the typical user friendly interfaces and the types of users who use each. (7)

 

Q.4 a. Differentiate between

(i)                  Procedural and non procedural languages.

(ii)                Key and superkey.

(iii)               Primary and secondary storage. (3 x 3)

b. With the help of an example show how records can be deleted and updated in QBE. (5)

 

Q.5 a. Describe cardinality ratios and participation constraints for relationship types. (4)

 

b. Information about a bank is about customers and their account. Customer has a name, address which consists of house number, area and city, and one or more phone numbers. Account has number, type and balance. We need to record customers who own an account. Account can be held individually or jointly. An account cannot exist without a customer.

Arrive at an E-R diagram. Clearly indicate attributes, keys, the cardinality ratios and participation constraints. (10)

 

 

 

 

Q.6 a. Describe the static hash file with buckets and chaining and show how insertion, deletion and modification of a record can be performed. (9)

 

b. What are the reasons for having variable length records? What types of separator characters are needed for each? (5)

 

PART II

Answer any THREE Questions. Each question carries 14 marks.

Q.7 Define the following terms

(i)                  Derived and stored attribute.

(ii)                Distributed system.

(iii)               Interblock gap.

(iv)              Degree of a relation.

(v)                Catalog.

(vi)              Conceptual schema.

(vii)             DDL and SDL. (7 x 2 = 14)

 

Q.8 a. Define a relation. (2)

 

b. Describe entity integrity and referential integrity. Give an example of each. (6)

 

c. Consider the two relations given below

R S

A

B

C

 

 

 

 

a1

b1

c1

 

D

A

F

null

b2

null

 

d1

a1

f1

a1

b1

c1

 

d1

a2

null

Given that A is the primary key of R, D is the primary key of S and there is a referential integrity between S.A and R.A, discuss all integrity constraints that are violated. (6)

 

Q.9 Given the following relations

 

TRAIN (NAME, START, DEST)

TICKET (PNRNO., START, DEST, FARE)

PASSENGER (NAME, ADDRESS, PNRNO.)

Write SQL expressions for the following queries:

(i)                  List the names of passengers who are travelling from the start to the destination station of the train.

(ii)                List the names of passengers who have a return journey ticket.

(iii)               Insert a new Shatabdi train from Delhi to Bangalore.

(iv)              Cancel the ticket of Tintin. (3.5 x 4 = 14)


 

Q.10 a. Define outer union operation of the relational algebra. Compute the outer union for the relations R ans S given below. (2+3)

 

R S

A

B

C

 

D

A

F

a1

b1

c1

 

d1

a1

f1

a3

b2

c2

 

d1

a2

null

 

b. Given the following relations

 

Vehicle (Reg_no, make, colour)

Person(eno, name, address)

Owner(eno, reg_no)

 

Write expressions in the relational algebra to answer the following queries:-

 

(i)                  List the reg_no of vehicles owned by John.

(ii)                List the names of persons who own maruti cars.

(iii)               List all the red coloured vehicles. (3 x 3)

 

Q.11 a. Describe DROP TABLE command of SQL with both the options CASCADE and RESTRICT. (5)

b. With respect to Oracle describe the following:

 

(i)                  Data Block.

(ii)                Data dictionary.

(iii)               Segments. (3 x 3)