Database Management Systems

a) Define the term 'data model'. Explain different types of data model. b) What is the goal of designing a database? Explain the overall database design and implementation process.

a) Explain, in brief, various constraints that can be placed on specialization and generalization. b) Explain aggregation with the help of a suitable example.

a) Explain not-null constraint. How does a not-null constraint enforce domain integrity? b) How are entity types and attributes mapped to relation schemas? Explain with the help of an example.

a) What is outer join operation? Explain how it differs from the inner join operation. b) Explain the division operation by giving an example.

a) What is functional dependency? Give examples. b) Explain the inference rules for functional dependencies.

a) What is transitive dependency? Explain the normal form based on the concept of transitive dependency. b) Consider a relation $R(A, B, C, D, E)$ with the functional dependencies $AB \rightarrow C, CD \rightarrow E$ and $DE \rightarrow B$. Is $AE$ a candidate key of this relation? If not, which is the candidate key? Explain.

List the steps followed by heuristic query optimizer to transform an initial query tree into an optimal query tree. Give a suitable example in support of your answer.

What is a precedence graph? How can it be used to test the conflict serializability of a schedule?

Explain two-phase locking protocol with the help of an example. What are its disadvantages? How can these disadvantages be overcome?

What are log-based techniques? Explain deferred- and immediate-modification versions of the log-based recovery technique with the help of an example.

Discuss the main characteristics of database approach. How it differs from traditional file system?

Discuss the major steps taken to setup a database for any enterprise.

Describe the overall structure of a general database management system.

Differentiate the following with examples : a) Weak entity set from Strong entity set b) Disjoint design constraint from Overlapping design constraint

Draw an E-R diagram for a college library where the following constraints are to be considered : a) Same author can write more than one book with unique ISBN. b) A publisher can publish more than one book. c) There are number of copies for same book with unique book code.

Design a generalization specialization hierarchy for a motor vehicle sales company. The company sales motorcycle, passenger cars, vans and buses. Justify your placement of attributes at each level of the hierarchy.

a) How do we represent a weak entity set in a relational model? b) Differentiate instance from schema.

a) Discuss select $(\sigma)$ and project $(\pi)$ operation with example. b) Differentiate inner join from outer join.

a) Explain that every candidate key is a super key but every super key may not be a candidate key. b) What do you mean by a foreign key?

Write the history of database system.