Q.81 Which of the following is not a consequence of non-normalized database?
(A) Update Anomaly (B) Insertion Anomaly
(C) Redundancy (D) Lost update problem
Ans: (D)
Q.82 Which of the following is true for relational calculus?
(A) ∀x(P(x))≡¬(∃x)(¬P(x)) (B) ∀x(P(x))≡¬(∃x)(P(x))
(C) ∀x(P(x))≡(∃x)(¬P(x)) (D) ∀x(P(x))≡(∃x)(P(x))
Ans: (A)
Q.83 The part of a database management system which ensures that the data remains in a
consistent state is
(A) authorization and integrity manager
(B) buffer manager
(C) transaction manager
(D) file manager
Ans: (C)
Q.84 Relationships among relationships can be represented in an-E-R model using
(A) Aggregation (B) Association
(C) Weak entity sets (D) Weak relationship sets
Ans: (A)
Q.85 In tuple relational calculus P1 AND P2 is equivalent to
(A) (¬P1OR¬P2). (B) ¬(P1OR¬P2).
(C) ¬(¬P1OR P2). (D) ¬(¬P1OR ¬P2).
AC14/AT11 Database Management Systems
13
Ans: (D)
Q.86 If α→β holds then so does
(A) γα→γβ (B) α→→γβ
(C) both (A) and (B) (D) None of the above
Ans: (A)
Q.87 Cascading rollback is avoided in all protocol except
(A) strict two-phase locking protocol.
(B) tree locking protocol
(C) two-phase locking protocol
(D) validation based protocol.
Ans: (D)
Q. 88 Wait-for graph is used for
(A) detecting view serializability. (B) detecting conflict serializability.
(C) deadlock prevention (D) deadlock detection
Ans: (D)
Q.89 The expression σθ1(E1 θ2E2) is the same as
(A) E1 θ1^ θ2E2 (B) σθ1 E1^σθ2 E2
(C) E1 θ1∨ θ2E2 (D) None of the above
Ans: (A)
Q.90 The clause alter table in SQL can be used to
(A) add an attribute
(B) delete an attribute
(C) alter the default values of an attribute
(D) all of the above
Ans: (D)
Q. 91 The data models defined by ANSI/SPARC architecture are
(A) Conceptual, physical and internal
(B) Conceptual, view and external
(C) Logical, physical and internal
(D) Logical, physical and view
Ans: (D)
Q.92 Whenever two independent one-to-many relationships are mixed in the same relation, a
_______ arises.
(A) Functional dependency (B) Multi-valued dependency
(C) Transitive dependency (D) Partial dependency
Ans:(B)
Q.93 A table can have only one
(A) Secondary key (B) Alternate key
(C) Unique key (D) Primary key
Ans: (D)
Q.94 Dependency preservation is not guaranteed in
(A) BCNF (B) 3NF
(C) PJNF (D) DKNF
Ans: (A)
Q.95 Which is the best file organization when data is frequently added or deleted from a file?
(A) Sequential (B) Direct
(C) Index sequential (D) None of the above
Ans: (B)
Q.96 Which of the following constitutes a basic set of operations for manipulating relational
data?
(A) Predicate calculus (B) Relational calculus
(C) Relational algebra (D) SQL
Ans: (C)
Q.97 An advantage of views is
(A) Data security (B) Derived columns
(C) Hiding of complex queries (D) All of the above
Ans: (A)
Q.98 Which of the following is not a recovery technique?
(A) Deferred update (B) Immediate update
(C) Two-phase commit (D) Shadow paging
Ans: (C)
Q.99 Isolation of the transactions is ensured by
(A) Transaction management (B) Application programmer
(C) Concurrency control (D) Recovery management
Ans: (C)
Q.100 _______ operator is used to compare a value to a list of literals values that have been
specified.
(A) Like (B) COMPARE
(C) BETWEEN (D) IN
Ans: (A)
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