A 3 NF relation is converted to BCNF by
1.removing composite keys
2.removing multivalued dependencies
3.dependent attributes of overlapping composite keys are put in a separate relation
4.dependent non-key attributes are put in a separate table
A 3 NF relation is split into 4 NF
1.by removing overlapping composite keys
2.by splitting into relations which do not have more than one independent multivalued dependency
3.removing multivalued dependency
4.by putting dependent non-key attribute in a separate table
A check pointing system is needed
1.to ensure system security
2.to recover from transient faults
3.to ensure system privacy
4.to ensure system integrity
A conceptual data model is converted using a Relational Data Base Management System to a
1.logical data model
2.external data model
3.internal data model
4.an entity-relation data model
A database administrator
1.administers data in an organization
2.controls all inputs and all outputs of programs
3.is controller of data resources of an organization
4.controls all data entry operators
A database is a
1.collection of files
2.collection of inputs and outputs of application
3.collection of related data necessary to manage an organization
4.data resource of an organization
A database models data so that it is
1.appropriate for application
2.independent of application program
3.optimized for most frequent applications
4.optimized for all applications
A database should be designed to allow providing
1.different views of portions of data requested by an application
2.data only to selected applications as decided by an organization
3.a uniform view of data to all applications
4.data to all applications
A DBMS
1.is a set of procedures
2.manages a database
3.is a set of procedures to manage a database to provide data as required by applications
4.provides data to applications
A DBMS is
1.another name for database system
2.independent of a database
3.dependent on application programs
4.is a set of procedures which manage a database
A query operation on a object
1.has side effect
2.has no side effects
3.changes the state of an object
4.is not allowed
A relation is said to be in BCNF when
1.it has overlapping composite keys
2.it has no composite keys
3.it has no multivalued dependencies
4.it has no overlapping composite keys which have related attributes
A relation which is in a higher normal form
1.implies that it also qualifies to be in lower normal form
2.does not necessarily satisfy the conditions of lower normal form
3.is included in the lower normal form
4.is independent of lower normal forms
A subset of logical data model accessed by programmers is called a
1.conceptual data model
2.external data model
3.internal data model
4.an entity-relation data model
A subsystem of a complex system must specify
1.what task it performs
2.how it performs a task
3.with which subsystems it co-operates
4.how it co-operates with other systems
Access right to a database is controlled by
1.top management
2.system designer
3.system analyst
4.database administrator
Attributes are assigned value
1.when operations are performed on an object
2.when instances of objects are defined
3.when methods are invoked
4.when classes are identified
By polymorphism of a subsystem we mean
1.it should be reusable
2.it should have polymorphic data types
3.it should accept generic commands and interpret appropriately
4.it should morph polygons
By redundancy in a file based system we mean that
1.unnecessary data is stored
2.same data is duplicated in many files
3.data is unavailable
4.files have redundant data
By relation cardinality we mean
1.number of items in a relationship
2.number of relationships in which an entity can appear
3.number of items in an entity
4.number of entity sets which may be related to a given entity
Computer systems are designed by
1.simplifying requirements of system
2.breaking of the system into smaller self-contained co-operating subsystems
3.breaking up the systems into independent parts
4.modular design
Data availability is often difficult in file based system
1.as files are duplicated
2.as unnecessary data are stored in files
3.as one has to search different files and these files may be in different update states
4.redundant data are stored in files 8.5.4 Management policy changes are difficult to implement in a file based system because
Data independence allows
1.sharing the same database by several applications
2.extensive modification of applications
3.no data sharing between applications
4.elimination of several application programs
Data integrity in a file based system may be lost because
1.the same variable may have different values in different files
2.files are duplicated
3.unnecessary data is stored in files
4.redundant data is stored in files
Data integrity is ensured by
1.good data editing
2.propagating data changes to all data items
3.preventing unauthorized access
4.preventing data duplication
DBMS
1.does not allow replication of data
2.allows controlled replication of data if it improves performance
3.does not allow common data to be duplicated
4.does not allow replication as it adversely affects reliability
Entities are identified from the word statement of a problem by
1.picking words which are adjectives
2.picking words which are nouns
3.picking words which are verbs
4.picking words which are pronouns
Fourth normal form (4 NF) relations are needed when
1.there are multivalued dependencies between attributes in composite key
2.there are more than one composite key
3.there are two or more overlapping composite keys
4.there are multivalued dependency between non-key attributes
Functions and procedures are
1.not useful in designing computer systems
2.old fashioned and they are not useful
3.useful in designing computer systems
4.have side effects which require special care if they are used as subsystems
Given a word statement of a problem potential objects are identified by selecting
1.verb phrases in the statement
2.noun phrases in the statement
3.adjectives in the statement
4.adverbs in the statement
Given a word statement of problem potential operations appropriate for objects are identified by selecting
1.verb phrases in the statement
2.noun phrases in the statement
3.adjectives in the statement
4.adverbs in the statement
Given an attribute x, another attribute y is dependent on it, if for a given x
1.there are many y values
2.there is only one value of y
3.there is one or more y values
4.there is none or one y value
Given the following relation vendor order ( vendor no, order no, vendor name, qty supplied, price/unit) it is not in 2 NF because
1.it is not in 1 NF
2.it has a composite key
3.non-key attribute vendor name is dependent on vendor no. which is one part of the composite key
4.Qty supplied and price/unit are dependent
Given the following relation it is not 3 NF because Student (roll no, name, course no, course max. marks, year of study, address)
1.it is not in 2 NF
2.it does not have composite key
3.non-key attributes course no and course max. marks are functionally dependent
4.it has more than 3 non-key attributes
If an entity appears in N relationships then it is
1.a 1:1 relationship
2.a 1:N relationship
3.a N:1 relationship
4.a N:M relationship
If an entity appears in not more than 5 relationships then it is a
1.1:1 relationship
2.1:5 relationship
3.5:1 relationship
4.5:5 relationship
In object-oriented design
1.operations and methods are identical
2.methods specify algorithms whereas operations only state what is to be done
3.methods do not change values of attributes
4.methods and constructor are same
In UML diagram of a class
1.state of object cannot be represented
2.state is irrelevant
3.state is represented as an attribute
4.state is represented as a result of an operation
Inheritance in object-oriented modelling can be used to
1.generalize classes
2.specialize classes
3.generalize and specialize classes
4.create new classes
Object-oriented system modelling using CRC method gives
1.Java programs for the system
2.C++ programs for the system
3.Classes of the system, their responsibilities and collaborating classes
4.Objective C programs for the system
Objects may be viewed as
1.clients in a system
2.servers in a system
3.as both clients and servers in a system
4.neither as clients nor as servers in a system
Pick entity set from the following
1.all vendors supplying to an organization
2.vendors and organizations they supply
3.vendors and transporters
4.a vendor supplying to many organizations
Relationships are identified from the word statement of a problem by
1.picking words which are adjectives
2.picking words which are nouns
3.picking words which are verbs
4.picking words which are pronouns
TEACHER-STUDENT relation in Mini-case example 2 is required because
1.it is in 3 NF
2.it has a multivalued key
3.it has a composite key with multivalued dependency relation
4.Without this relation database is incomplete and some queries cannot be answered
The attributes of relationship teaches in teacher teaches course should be
1.teacher code, teacher name, dept, phone no
2.course no, course name, semester offered, credits
3.teacher code, course no, semester no
4.teacher code, course no, teacher name, dept, phone no
The columns of a relation
1.must be in specified order
2.may be in any order
3.with key field in first column
4.with largest width column last
The entity set is a
1.set of entities
2.collection of different entities
3.collection of related entities
4.collection of similar entities
The expansion of the acronym CRC is
1.Collecting Responsibilities Classes
2.Collaborating with Relevant Classes
3.Class Responsibilities and Collaborators
4.Creating Relevant Classes
The project guidance relation of Exercise 10.8.3 needs further normalization to 5 NF because
1.There are too many multivalued dependencies
2.Multivalued dependency and simple dependency are mixed in the 4 NF relation
3.Spurious tuples got introduced when the 4 NF relations are combined due to the fact that a professor can guide only specified projects
4.4 NF relations have composite keys
The rows of a relation
1.must be in specified order
2.may be in any order
3.in ascending order of key
4.in descending order of key