DBMS-1 (Multiple Questions & Answers)
1)____________is statement that is executed automatically by the system
as a side effect of a modification of a database.
A) Assertion
B) Trigger
C)cursor
D) None
Ans: B
2) A collection of conceptual tools for describing data, data relationships,
data semantics, consistency constraints is__________.
A) Data model
B) ER model
C) Object based model
D) None
Ans: A
3) The overall design of a database is called___________.
A) Database design
B) Instance
C) Schema
D) None
Ans: C
4) Every determinant is a key. This is____________.
A) 2NF
B) BCNF
C) 3NF
D) 1NF
Ans: B
5)__________is a set of one or more attributes, that taken collectively allows
us to identify uniquely an entity in entity set.
A) Super key
B) Candidate key
C) Primary key
D) None
Ans: A
6) The time of locks by which a data item can be locked are
A) Shared
B) Exclusive
C) Both
D) None
Ans: C
7)__________is the highest level of abstraction describes only that part of
the entire database.
A) Physical level
B) Logical level
C) View level
D) None
Ans: C
8)Part of a super key is__________
A) Candidate key
B) Primary key
C) Alternate key
D) None
Ans: C
9)_________refers to the disk mirroring.
A) RAID level 0
B) RAID level 1
C) RAID level 2
D) RAID level 3
Ans: B
10) The disadvantage of relational database design are:
A) Repetition of information
B) Inability to represent data
C) Only A
D) Both
Ans: D
11) There are _____different types of serializability
A) 1
B) 2
C) 3
D) None
Ans: A
12) A primary key with more than one attribute is called
A) Candidate key
B) Composite key
C) Alternate key
D) None
Ans: B
13) Tuple relational calculus is _______query language.
A) Procedural
B) Non procedural
C) Structured
D) None
Ans: B
14)_________express the number of entities to which another entity can be
associated via a relationship set
A) Cardinality ratio
B) Mapping cardinalities
C) Both
D) None
Ans: C
15) ________ is a particular property, which describes the entity.
Attribute
Entity
C) Object
D) None
Ans: A
16) ________ types of Data Independence are present.
A) 3
B) 2
C) 1
D) None
Ans: B
17)__________ is the time from when a read or write request is issued to when
data transfer begins.
A) Average seek time
B) Access time
C) Latency time
D) None
Ans: B
18) The property ‘Either all operations of the transaction are reflected
properly in the database’ refers to
A) Durability
B) Atomicity
C) Isolation
D) None
Ans: B
19) A transaction that completes it execution successfully is called ______.
A) Aborted
B) Committed
C) Partially commited
D) Failed
Ans: B
20) In a two phase locking protocol the phases are________.
A) Growing
B) Shrinking
C) Both
D) None
Ans: C
21.Given two union compatible relations R1(A,B) and R2(C,D)
what is the result of the operation R1 A=C AB=D R2 ?
a.R1 U R2 b. R1 ^ R2 c.R1 - R2 d.R1 * R2
Ans:B
22.The data dictionary tells the DBMS
a.What files are in the database b.What attributes are possessed by the data
c.What these files contain d.All of the above
Ans:D
23. The level of abstraction describes only part of the
entries database is called
a. Physical level b.Conceptual level c.View level d.Procedural level
Ans:C
24.Identify the false statement
a.Hierarchical model evolved from the base system
b.Hierarchical model is super set of network model
c.network model is a super set of Hierarchical model
d.Relational model is based on the mathematical model of relation
Ans:B
25.With regard to the expressive power of the formal relational
query languages which of the following statement is TRUE
a. Relational algebra is more powerful than relational calculus
b. Relational algebra is same power as relational calculus
c. Relational algebra is same powerful as safe relational calculus
d. None of these
Ans:C
26.Suppose the adjacency relation of vertices in a graph is represented
in a table Adj(x,y) which of the following queries can not be
expressedby a relational algebra expressions of constant length?
a.List of all vertices adjacent to a given matrix
b.List of all vertices which have self loops
c.List of all vertices which belong to cycle of less than three vertices.
d.List of all vertices reachable from a given vertex
Ans:D
27.Consider the schema R=(S T U V) and the dependencies S->T, T->U,
U->V and V-> S. Let (R1 and R2) be a decomposition such that
R1-> R2={}(null set). The decomposition is:
a.not in 2NF b.in 2 NF but not in 3 NF
c.In 3 NF but not in 2 NF d.In both the 2NF and 3NF
Ans:D
28.Given the functional dependencies x->w; x->y; y->Z and Z->pq
which of the following does not hold good?
a.x->Z b.W->Z c.X->WY d. None
Ans:B
29.Every determinant should be a candidate key is the definition of
---------- Normal form:
a. Project-join NF b.Second NF c.BCNF d.3NF
Ans:C
30.Blocking factor refers to
a.The number of blocks that can be accommodated in a sector
b.The number of records that can be accommodated in a block
c. The number of blocks into which the file is divided
d.The number of files that can fit into a single block
Ans:B
31.In Query-Ny-Example, the query formed from
the relations displayed by filling in the following.
a.SQL form b.Templates c.DML d.DDL
Ans:B
32.SQL is relationally?
a. complete language b.incomplete language
c.Cant handle certain relations d.Sound language
Ans:A
33.Given relations r(w,x) and s(y,z) the result of
Select distinct w,x from r, s is guaranteed to be the same as r, provided:
a.r has no duplicates and is non-empty
b.r and s have no duplicates
c.s has no duplicates and r is non empty
d.r and s have the same number of tuples
Ans:A
34.In SQL relations can contain null values, and comparisons with null values
are treated as unknown suppose all comparisons with a null value are
treated as false. Which of the following pairs is not equivalent?
a.x=5 not (not(x=5)) b.x=5 x>4 and x<6, where x is an integer
c.x!=5 and not(x=5) d. none
Ans:C
35.Relation R is decomposed using a set of functional dependencies F,
and relation S is decomposed using another set of functional
dependencies, G.One decomposition is definitely BCNF, the other is
definitely 3NF, but it is not know which is which. To make
guaranteed identification, which one of the following tests
should be used on the decompositions?
(Assume the closure of F and G are available)
a.Dependency-preservation b.Lossless-Join
c.BCNF definition d.3NF definition
Ans:B
36.From the following instance of a relation schema R(A,B,C), we can
conclude that
A B C
1 1 1
1 1 0
2 3 2
2 3 2
a.A functionally determines B and B functionally determines C
b.A functionally determines B and B does not functionally determine C
c.B does not functionally determine C
d.A does not functionally determines B and B does not functionally determine C
Ans:A
37.The level of abstraction describes only part of the entries database is called
a.Physical level b.Conceptual level c.View level d.Procedural level
Ans:C
38.The maximum height of a B+ tree of order n with k key value is
a.(n+k)/2 b. log nk c.log n/2 (k/2+1) d.Log k/2n
Ans:C
39.Which of the following are correct
a.Range queries are faster on B+ tress
b. B-trees are for storing data on disk and B+ tress are for main memory
c.B-trees are for primary indexes and b+ trees are for secondary indexes
d.The height of a B+ tress is independent of the number of records
Ans:A
40.The file organization techniques which includes an
index on every secondary field is :
a.Inverted organization b.Multi list Organization
c.Regular Organization d. Hierarchical organization
Ans:A
41.The database and DBMS software together is called as?
a.Database System b.Database Management System c.Data software d.none
Ans:A
42.The highest level of abstraction describes only part of entire database?.
a.Physical level b.Logical level c.View level d.None
Ans:C
43. The level of abstraction describes how data are stored.?
a.Physical level b.Logical level c.View level d.None
Ans:A
44.?The application is independent of the storage structure
and access strategy of data? is called ?
a.Data Independence b.Physical Data Independence
c.Logical Data Independence d.none
Ans:A
45.A collection of conceptual tools for describing data, data
relationships data semantics and constraints is called?
a.Data Model b.E-R model c.View d.none
Ans:A
46.The collection (set) of entities that have same attributes is called?
a.Entityset b.Entity c.Entity type d.none
Ans:C
47.What is an Extension of entity type?
a.collection of all entities of particular entity type in the database.
b.collections of entities of a particular entity type are grouped together
into an entity set.
c.collection (set) of entities that have same attributes.
d.It is a 'thing' in the real world with an independent existence.
Ans:B
48.The number of entity type participating is called?.
a.Relationship type b.Relationship set
c.degree of a Relation d.degree of Relationship type
Ans:D
49.A data base schema is specifies by a set of definitions
expressed by a special language called ?
a.View Definition Language b.Data Definition Language
c.Storage Definition Language d.none
Ans:B
50.The language that is to specify the internal schema is..?
a.View Definition Language b.Data Definition Language
c.Storage Definition Language d.none
Ans:C
51.Extend DML
a.Data Multiple Language b.Data Manipulation Language
c.Data Multiplex Language d.Data Model Language
Ans:B
52.Which of the following executes low-level instruction
generated by compiler.. ?
a.DML Compiler b.DDL Interpreter
c.Query evaluation engine d. Non-Procedural DML
Ans:C
53.The process of analysing the given relation schemas based
on their Functional Dependencies (FDs) and primary key
to achieve the properties is..?
a.normalization b.Functional Dependency
c.Multivalued dependency d.none
Ans:A
54.The domain of attribute must include only atomic
(simple, indivisible) values in
a.1 NF b.2 NF c.3 NF d.4NF
Ans:A
55.What is BCNF (Boyce-Codd Normal Form)?
a.relation schema R is in BCNF if it is in 1NF and satisfies
an additional constraint that for every FD X A, X must
be a candidate key
b.relation schema R is in BCNF if it is in 2NF and satisfies an
additional constraint that for every FD X A, X must
be a candidate key
c.relation schema R is in BCNF if it is in 4NF and satisfies an
additional constraint that for every FD X A, X
must be a candidate key
d.relation schema R is in BCNF if it is in 3NF and satisfies an
additional constraint that for every FD X A, X
must be a candidate key
Ans:D
56.Advantages of DBMS?
a.Redundancy is controlled b.Enforcing integrity constraints.
c.Data isolation. d.Both Redundancy is controlled & Enforces integrity constraints
Ans:D
57.The number of tuples present in a table at any instance is called?
a.Intension b.Extension
c.Both Intension & Extension d.Neither Intension nor Extension
Ans:B
58.Which Data Independence is more difficult to achieve?
a.Physical Data Independence b.Logical Data Independence
c.Both Physical Data Independence & Logical Data Independence
d.can't say exactly
Ans:B
59.DML requires a user to specify what data are needed
without specifying how to get those data is...?
a.High level DML b.Non-Procedural DML
c.Procedural DML d.Both High level DML & Non-Procedural DML
Ans:D
60.DML requires a user to specify what data are needed
and how to get those data.
a.High level DML b.Non-Procedural DML
c.Procedural DML d.Both High level DML & Non-Procedural DML
Ans:C
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