Q.31 If the closure of an attribute set is the entire relation then the attribute set is a
(A) superkey (B) candidate key
(C) primary key (D) not a key
Ans: (A)
Q.32 DROP is a ______________ statement in SQL.
(A) Query (B) Embedded SQL
(C) DDL (D) DCL
Ans: (C)
Q.33 If two relations R and S are joined, then the non matching tuples of both R and S are
ignored in
(A) left outer join (B) right outer join
(C) full outer join (D) inner join
Ans: (D)
Q.34 The keyword to eliminate duplicate rows from the query result in SQL is
(A) DISTINCT (B) NO DUPLICATE
(C) UNIQUE (D) None of the above
` Ans: (C)
Q.35 In 2NF
(A) No functional dependencies (FDs) exist.
(B) No multivalued dependencies (MVDs) exist.
(C) No partial FDs exist.
(D) No partial MVDs exist.
Ans: (C)
Q.36 Which one is correct statement?
Logical data independence provides following without changing application programs:
(i) Changes in access methods.
(ii) Adding new entities in database
(iii) Splitting an existing record into two or more records
(iv) Changing storage medium
(A) (i) and (ii) (B) (iv) only, (C) (i) and (iv) (D) (ii) and (iii)
Ans: (D)
Q.37 In an E-R, Y is the dominant entity and X is a subordinate entity. Then which of the
following is incorrect :
(A) Operationally, if Y is deleted, so is X
(B) existence is dependent on Y.
(C) Operationally, if X is deleted, so is Y.
(D) Operationally, if X is deleted, & remains the same.
Ans: (C)
Q.38 Relational Algebra is
(A) Data Definition Language .
(B) Meta Language
(C) Procedural query Language
(D) None of the above
Ans: (C)
Q.39 Which of the following aggregate functions does not ignore nulls in its results?.
(A) COUNT . (B) COUNT (*)
(C) MAX (D) MIN
Ans: (B)
Q.40 R (A,B,C,D) is a relation. Which of the following does not have a lossless join
dependency preserving BCNF decomposition
(A) A B, B CD (B) A B, B C, C D .
(C) AB C, C AD (D) A BCD
Ans: (D)
Q.41 Consider the join of relation R with a relation S. If R has m tuples and S has n
tuples, then the maximum and minimum size of the join respectively are
(A) m+n and 0 (B) m+n and |m-n|
(C) mn and 0 (D) mn and m+n
Ans: (C)
Q.42 Maximum height of a B+ tree of order m with n key values is
(A) Logm(n) (B) (m+n)/2
(C) Logm/2(m+n) (D) None of these
Ans: (D)
Q.43 Which one is true statement :
(A) With finer degree of granularity of locking a high degree of concurrency is
possible.
(B) Locking prevents non – serializable schedules.
(C) Locking cannot take place at field level.
(D) An exclusive lock on data item X is granted even if a shared lock is already
held on X.
Ans: (A)
Q.44 Which of the following statement on the view concept in SQL is invalid?
(A) All views are not updateable
(B) The views may be referenced in an SQL statement whenever tables are
referenced.
(C) The views are instantiated at the time they are referenced and not when they
are defined.
(D) The definition of a view should not have GROUP BY clause in it.
Ans: (D)
Q.45 Which of the following concurrency control schemes is not based on the
serializability property?
(A) Two – phase locking (B) Graph-based locking
(C) Time-stamp based locking (D) None of these .
Ans: (D)
Q.46 Which of the following is a reason to model data?
(A) Understand each user’s perspective of data
(B) Understand the data itself irrespective of the physical representation
(C) Understand the use of data across application areas
(D) All of the above
Ans: (D)
Q.47 If an entity can belong to only one lower level entity then the constraint is
(A) disjoint (B) partial
(C) overlapping (D) single
Ans: (B)
Q.48 The common column is eliminated in
(A) theta join (B) outer join
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(C) natural join (D) composed join
Ans: (C )
Q.49 In SQL, testing whether a subquery is empty is done using
(A) DISTINCT (B) UNIQUE
(C) NULL (D) EXISTS
Ans: (D)
Q.50 Use of UNIQUE while defining an attribute of a table in SQL means that the attribute
values are
(A) distinct values (B) cannot have NULL
(C) both (A) & (B) (D) same as primary key
Ans: (C)
Q.51 The cost of reading and writing temporary files while evaluating a query can be reduced
by
(A) building indices (B) pipelining
(C) join ordering (D) none of the above
Ans: (B)
Q.52 A transaction is in __________ state after the final statement has been executed.
(A) partially committed (B) active
(C) committed (D) none of the above
Ans: (C)
Q.53 In multiple granularity of locks SIX lock is compatible with
(A) IX (B) IS
(C) S (D) SIX
Ans: (B)
Q.54 The statement that is executed automatically by the system as a side effect of the
modification of the database is
(A) backup (B) assertion
(C) recovery (D) trigger
Ans: (D)
Q.55 The normal form that is not necessarily dependency preserving is
(A) 2NF (B) 3NF
(C) BCNF (D) 4NF
Ans: (A)
Q.56 A functional dependency of the form x → y is trivial if
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(A) y ⊆ x (B) y ⊂ x
(C) x ⊆ y (D) x ⊂ y
Ans: (A)
Q.57 The normalization was first proposed by ______________.
(A) Code (B) Codd
(C) Boyce Codd (D) Boyce
Ans: (B)
Q.58 The division operator divides a dividend A of degree m+n by a divisor relation B of
degree n and produces a result of degree
(A) m – 1 (B) m + 1
(C) m * m (D) m
Ans: (D)
Q.59 Which of the following is not a characteristic of a relational database model?
(A) Table (B) Tree like structure
(C) Complex logical relationship (D) Records
Ans: (B)
Q.60 Assume transaction A holds a shared lock R. If transaction B also requests for a shared
lock on R.
(A) It will result in a deadlock situation.
(B) It will immediately be rejected.
(C) It will immediately be granted.
(D) It will be granted as soon as it is released by A .
Ans: (C)
Q.61 In E-R Diagram total participation is represented by
(A) double lines (B) Dashed lines
(C) single line (D) Triangle
Ans: (A)
Q.62 The FD A → B , DB → C implies
(A) DA → C (B) A → C
(C) B → A (D) DB → A
Ans: (A)
Q.63 The graphical representation of a query is ________.
(A) B-Tree (B) graph
(C) Query Tree (D) directed graph
Ans: (C)
Q.64 Union operator is a :
(A) Unary Operator (B) Ternary Operator
(C) Binary Operator (D) Not an operator
Ans: (C)
Q.65 Relations produced from an E-R model will always be
(A) First normal form. (B) Second normal form.
(C) Third normal form. (D) Fourth normal form.
Ans: (A)
Q.66 Manager salary details are hidden from the employee .This is
(A) Conceptual level data hiding.
(B) External level data hiding.
(C) Physical level data hiding.
(D) None of these.
Ans: (A)
Q.67 Which of the following is true for network structure?
(A) It is a physical representation of the data.
(B) It allows many to many relationship.
(C) It is conceptually simple.
(D) It will be the dominant database of the future.
Ans: (A)
Q.68 Which two files are used during operation of the DBMS?
(A) Query languages and utilities
(B) DML and query language
(C) Data dictionary and transaction log
(D) Data dictionary and query language
Ans: (C )
Q.69 A list consists of last names, first names, addresses and pin codes. If all people in the
list have the same last name and same pin code a useful key would be
(A) the pin code
(B) the last name
(C) the compound key first name and last name
(D) Tr from next page
Ans: (C )
Q.70 In b-tree the number of keys in each node is ____ than the number of its children.
(A) one less (B) same
(C) one more (D) half
Ans: (A)
Q.71 The drawback of shadow paging technique are
(A) Commit overhead (B) Data fragmentation
(C) Garbage collection (D) All of these
Ans: (D)
Q.72 Which normal form is considered adequate for normal relational database design?
(A) 2NF (B) 5NF
(C) 4NF (D) 3NF
Ans: (D)
Q.73 Which of the following addressing modes permits relocation without any change over
in the code?
(A) Indirect addressing (B) Indexed addressing
(C) PC relative addressing (D) Base register addressing
Ans: (B)
Q.74 In a multi-user database, if two users wish to update the same record at the same time,
they are prevented from doing so by
(A) jamming (B) password
(C) documentation (D) record lock
Ans: (D)
Q.75 The values of the attribute describes a particular_____________
(A) Entity set (B) File
(C) Entity instance (D) Organization
Ans: (C)
Q.76 Which of the following relational algebraic operations is not from set theory?
(A) Union (B) Intersection
(C) Cartesian Product (D) Select
Ans: (D)
Q.77 Which of the following ensures the atomicity of the transaction?
(A) Transaction management component of DBMS
(B) Application Programmer
(C) Concurrency control component of DBMS
(D) Recovery management component of DBMS
Ans: (A)
Q.78 If both the functional dependencies : X→Y and Y→X hold for two attributes X and Y
then the relationship between X and Y is
(A) M:N (B) M:1
(C) 1:1 (D) 1:M
Ans: (C)
Q.79 What will be the number of columns and rows respectively obtained for the operation, AB,
if A B are Base union compatible and all the rows of a are common to B? Assume A
has 4 columns and 10 rows; and B has 4 columns and 15 rows
(A) 4,0 (B) 0,0
(C) 4,5 (D) 8,5
Ans: (A)
Q.80 For correct behaviour during recovery, undo and redo operation must be
(A) Commutative (B) Associative
(C) idempotent (D) distributive
Ans: (C)
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