Database Management System - Old Questions

2. What is database? Discuss the importance of DBMS.

3. Define union compatibility. Given following relations, show the resulting relation of Director  Actor and Actor U Director?

Director 

 Actor 

5. How Order By and Group By Having Clause in SQL are different? Illustrate with suitable examples.

6. Why normalization is needed? When any relation is said to be in 1NF and 2NF?

7. How cost of query is measured during query processing? Construct query expression tree for relational algebra query;

8. How wait-for-graph is constructed? How can you use it to detect deadlock in a schedule of transactions? Support your answer with an example.

9. How read and write operations are performed in a transaction? List the various states where transactions can enter into.