DATABASE MANAGEMENT SYSTEM

A row from a table is selected by

• (i) selection operator
• (ii) projection operator
• (iii) union operator
• (iv) none of these

__________ operations do not preserve non-matched tuples.

• (i) Inner join 
• (ii) Left outer join 
• (iii) Query 
• (iv) Relational schema

A normal form in which every non-prime attribute is fully dependent on prime attribute is

• (i) 1 NF
• (ii) 2 NF
• (iii) 3 NF
• (iv) BCNF

Which of the following operations is used if we are interested in only certain columns of a table?

• (i) PROJECTION
  (ii) SELECTION
  (ii) UNION
  (iv) JOIN

Which of the following is the original purpose of SQL?

• (i) To specify the syntax and semantics of SQL data definition language
  (ii) To specify the syntax and semantics of SQL manipulation language
  (ii) To define the data structures
  (iv) All of the above

BCNF stands for

• (i) Boyle Cold Normalization Form
• (ii) Boyce Cold Normal Form
• (iii) Boyce Codd Normal Form
• (iv) None of these

Which of the following is used at the end of the view to reject the tuples which do not satisfy the condition in where clause?

• (i) With
  (ii) Check
  (iii) With check
  (iv) All of the above

The ability to query data, as well as insert, delete, and alter tuples, is offered by:

• (i) TCL (Transaction Control Language)
• (ii) DCL (Data Control Language)
• (iii) DDL (Data Definition Language)
• (iv) DML (Data Manipulation Language)

Which join refers to join records from the right table that have no matching key in the left table and are included in the result set?

• (i) Left outer join
  (i) Right outer join
  (iii) Full outer join
  (iv) Half outer join

Which command is used to remove a relation from SQL?

• (i) Drop table 
• (ii) Delete 
• (iii) Purge 
• (iv) Remove

Discuss about different keys used in database design with examples

Write an SQL query to retrieve all employees from an "Employees" table with specific criteria (e.g., department, salary range).

Explain the following operations with the help of examples:

• (i) Set of intersection operation
  (ii) Natural join operation
  (iii) Division operation

Define the process of database normalization and its importance in maintaining d integrity

Difference between Relational Algebra & Calculus.

Find the highest normal form of a relation R(ABCD) with FD set
(B→A, A→C, BC→D, AC→BE).

A relation R(A,C,D,E,H) is having two functional dependencies sets F={A→C, AC→D, E→AD, E→H} and set G {AC→D, E→AH}, then check F and Gare equivalent or not.

Describe the importance of data integrity in a database. How can constraints (such as primary keys and foreign keys) help enforce integrity?