81. A candidate key for the relation in a Database Management System can be defined as:

(a) The subset of the set of fields in a key which is a unique identifier for a tuple
(b) A set of fields that uniquely identifies a tuple according to the key constant
(c) Two tuples which have identical values in all the fields
(d) A field of relation is a unique identifier for a tuple

Answer: (b)

82. The conceptual schema is the collection of schemes of the relations stored in
(a) Tables
(b) Database
(c) Decision tree
(d) Files

Answer: (b)

83. In Database Management System (DBMS) architecture, the buffer manager is the software layer which is responsible for:
(a) Bringing pages from disk to the main memory
(b) Holding the slot of the page
(c) Transferring the pages to primary memory
(d) Sequencing the pages

Answer: (a)

84. A data structure that organizes the data records on a disk to optimize certain kinds of retrieval operations is known as:
(a) Decision tree
(b) Indexing
(c) File allocation tables
(d) Records

Answer: (b)

85. Which of the following operation is/are used in the equality operators to join the two relations?
1. Normal join
2. Equijoin

(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Answer: (b)

86. The query optimization in Database Management System (DBMS) is responsible for identifying:
(a) An efficient execution plan with the least estimated cost
(b) The tuples and fields
(c) The number of records present in database
(d) The non-relationship of the database

Answer: (a)

87. Which of the following rules is/are associated with Armstrong’s Axioms for finding the functional dependency(FD)?
1. Reflexivity
2. Augmentation
3. Transitivity

(a) 1, 2 and 3
(b) 1 only
(c) 2 only
(d) 3 only

Answer: (a)

88. Fourth Normal Form (4NF) is designed to cope up with:
(a) Multivalued dependency
(b) Join dependency
(c) Transitive dependency
(d) Both Join and Transitive dependency

Answer: (a)

89. Information warfare must be dealt with:
(a) Continuously because the potential damage or disruption is so high
(b) Immediately because the potential damage or disruption is so high
(c) Ahead of time because the potential damage or disruption is so high
(d) Diplomatically because the potential damage or disruption is so high

Answer: (c)

90. While national power grid may be necessary for transmitting huge blocks of power from one region to the other, which one of the following systems would still be required to serve the large number of villages and isolated communities?
(a) Grid connected stand alone
(b) Non- grid connected stand alone
(c) Grid connected service
(d) Non-grid connected service

Answer: (b)