CS-15 : RELATIONAL DATABASE MANAGEMENT SYSTEM DEC 1997

 

Time : 3 hours

Max.Mark : 75

Note : There are six questions in this paper.  Question 1 us compulsory and carries 30 marks.  Attempt any three from the rest.

1. (a) Draw an E-R diagram for a Hospital System.  Convert this diagram to a suitable relational schema.
  (b) Convert the following query in domain calculus to relational algebra, tuple calculus and English words
    {<A, B> | < A, B> BELONGS rel1 6B = 'B1' VB = 'B2'}
  (c) What is view ?  What are the problems associated with an update operation of RDBMS if it is to be performed using views ?
  (d) Explain the sort and merge method of Query evaluation.
  (e) What is a Log in RDBMS ?  what is write-ahead log-strategy ?  How is this strategy useful in recovery of centralised databases ?
  (f) what is intention-mode locking ?  Explain various locks used for locking a hierarchical structure of database.
2.   Write short notes on the following :
  (a) Statistical Databases
  (b) Access matrix and query modification
  (c) Atomicity of Transaction
  (d) Phantom phenomenon
  (e) Cascading rollback
3. (a) What is prenex normal form for a query ?  Explain with the help of an example.
  (b) What are the basic components of a Query Processor ?  Discuss.
  (c) What are the states of a Transaction ?  Discuss.
4. (a) What is shadow paging scheme for database recovery ?
  (b) Describe the time-stamp based concurrency management scheme.
5. (a) A relation X { A,B,C,D,E,F,G,H} is having functional dependences as
    {ABCDEFGH,
BCD AEFGH,
BCE ADEFGH,
CE H,
CD H}
Develop the normalised relational scheme of the relation.
  (b) Define the following terms :
    (i)   Access Plan
(ii)  Join Selectivity
(iii) Join Indexes
(iv) Serializable Schedule
(v) Two phase locking protocol
6.   Write short notes on the following in the context of RDBMS :
  (a) Triggers and Referential Integrity
  (b) Relational Algebra versus Relational Calculus
  (c) Embedded Data Manipulation Language
  (d) Archival Databases
  (e) Disaster Recovery
  (f) Transaction Redo
  (g) Check Pointing