CS403 Midterm Online Quiz

2 votes, 5 avg

CS403-Midterm

1 / 50

Consider the following statements.
A. Conceptual schema which is the result of conceptual design is a logical description of all data elements and their relationships.
B. Internal level of the database architecture consists of the physical view of the database.
C. External level of the database architecture provides the user view of the database.
With respect to the ANSI/SPARC three level database architecture, which of the above is/are correct?

Only A.

Only C.

Only B and C.

Only A and B.

2 / 50

Database management systems, operating systems, applications and utilities are all examples of ____.

software

hardware

computer infrastructure

input and output

3 / 50

Which of the following is true about relational schema?

Contains only derived attributes.

The sequence of rows is significant.

The sequence of columns is significant

Values are atomic.

4 / 50

A software package designed to store and manage databases

Data model

Data

Database

DBMS

5 / 50

Which of the following is a correct way to implement one-to-many relationship while designing tables?

by splitting the data into two tables with primary key and foreign key relationships

as a single table and rarely as two tables with primary and foreign key relationships

by splitting each table into three

using a junction table with the keys from both the tables forming the composite primary key of the junction table.

6 / 50

Identify the correct statement.

Referential integrity constraints check whether the primary key values are unique.

Referential integrity constraints check whether an attribute value lies in the given range.

When Referential integrity rules are enforced, a tuple in one relation that refers to another relation must refer to an existing tuple.

Referential integrity constraints are specified between entities having recursive relationships.

7 / 50

Which of the following statements is NOT correct?

The functional dependency EmpNo -> DeptNo holds over R.

The functional dependency ProjNo -> DeptNo holds over R.

The functional dependency (EmpNo, DeptNo) -> ProjNo holds over R.

The functional dependency (EmpNo, ProjNo) -> DeptNo holds over R.

8 / 50

Which of the following is not true about relational tables?

Each column must have a unique name.

Column values are of the same kind.

The sequence of rows is significant.

Each row is unique.

9 / 50

Which of the following statements is NOT correct?

The functional dependency EmpNo -> DeptNo holds over R.

The functional dependency (EmpNo, ProjNo) -> DeptNo holds over R

The functional dependency ProjNo -> DeptNo holds over R.

The functional dependency DeptNo -> ProjNo holds over R.

10 / 50

Which relational algebra operation could have been applied on the pair of relations Student and Instructor to obtain the above data?

Student – Instructor

Student ∩ Instructor

Instructor ÷ Student

Instructor – Student

11 / 50

Which of the following statements is NOT correct?

The functional dependency ProjNo -> DeptNo holds over R.

The functional dependency (EmpNo, ProjNo) -> DeptNo holds over R.

The functional dependency EmpNo -> DeptNo holds over R.

The functional dependency (EmpNo, DeptNo) -> ProjNo holds over R.

12 / 50

Which of the following functions are NOT performed by a database administrator?

Communicating with database users

Planning, designing and implementing database systems

Allocation of storage locations and data structures

Establishing standards and procedures for database systems

13 / 50

Which of the following is true about relational schema?

The sequence of columns is significant

The sequence of rows is significant.

Values are atomic.

Contains only derived attributes.

14 / 50

Which of the following constraints enforces entity integrity?

CHECK

PRIMARY KEY

FOREIGN KEY

NOT NULL

15 / 50

Consider the following statements.
A. An entity integrity constraint states that no primary key value can be null.
B. A referential integrity constraint is specified between two relations.
C. A foreign key cannot be used to refer to its own relation.
Identify which of the above statements is/are correct.

Only A

A and B

Only B

B and C

16 / 50

Identify the INCORRECT statement among the given

Age can be considered as a single value attribute of a person.

An entity type describes the schema or intension for a set of entities which share the same structure.

An entity may be an object with a physical existence like a car, a house or an Employee.

One cannot consider something which has conceptual existence like a course in a degree program as an entity.

17 / 50

Structural constraints of a relationship type refer to

the constraints applicable in granting access to tables, columns and views in a database schema.

whether the existence of an entity depends on it being related to another entity via the relationship type.

the role that a participating entity from the entity type plays in each relationship instance.

identifying the owner entity type relevant to a given entity type

18 / 50

Select the correct statement among the following.

When different entity types participate only once in a single relationship type it is called a recursive relationship

Role names are not technically necessary in relationship types when all the participating entity types are distinct.

Partial participation which is also called existence dependency is displayed as a double line connecting the participating entity type to the relationship.

Cardinality ratios for binary relationship are displayed on Entity Relationship Diagrams by using a diamond shape notation

19 / 50

In a conceptual model for a university, what type of relationship exists between Grade and Student entities?

1:01

M:M

1:M

Ternary

20 / 50

Which of the following constraints enforces entity integrity?

NOT NULL

PRIMARY KEY

CHECK

FOREIGN KEY

21 / 50

B and C

Only B

Only A

A and B

22 / 50

Which of the following constraints enforces entity integrity?

FOREIGN KEY

PRIMARY KEY

CHECK

NOT NULL

23 / 50

Structural constraints of a relationship type refer to

the role that a participating entity from the entity type plays in each relationship instance.

identifying the owner entity type relevant to a given entity type

the constraints applicable in granting access to tables, columns and views in a database schema.

whether the existence of an entity depends on it being related to another entity via the relationship type.

24 / 50

User rights information is stored in

Logical database

Buffer

Physical database

Catalog

25 / 50

The ____ constraint specifies whether each entity supertype occurrence must also be a member of at least one subtype.

uniqueness

completeness

specialization

inheritance

26 / 50

A collection of related data is

Data

Logical model

Relational model

Database

27 / 50

The ER- data model is an example of:

Logical database

Conceptual database

Physical database

Relational database

28 / 50

Which of the following is not a benefit of normalization?

Minimize updation anomolies

Minimize deletion anomolies

Minimize insertion anomolies

Maximize redundancy

29 / 50

Controlling redundancy in a database management system DOES NOT help to

avoid unnecessary wastage of storage space

avoid unauthorised access to data

avoid duplication

avoid inconsistency among data

30 / 50

A ____ relationship exists when an association is maintained within a single entity.

ternary

binary

weak

unary

31 / 50

Which of the following is true about NOT NULL constraint?

limit the values that can be placed in a column

enforce domain integrity

prevents any actions that would destroy links between tables with the corresponding data values

enforces the uniqueness of the values in a set of columns

32 / 50

Which of the following is INCORRECT statement concerning the database design process?

During requirements collection and analysis phase, one can gather the data requirements of database users.

By referring to a high level data model, it is possible to understand the data requirements of the users, entity types, relationships and constraints

During the logical design phase of internal storage structures, access paths and file organization for the database files are specified

Transformation of the high level data model into the implementation data model is called logical design or data model mapping

33 / 50

Identify the correct way to implement one-to-one relationship in tables?

as a single table and rarely as two tables with primary and foreign key relationships.

using a junction table with the keys from both the tables forming the composite primary key of the junction table.

by creating two separate tables

by splitting the data into two tables with primary key and foreign key relationships.·

34 / 50

Which feature of database provides conversion from inconsistent state of DB to a consistent state ensuring
minimum data loss?

User accessible catalog

Authorization service

Data processing

Recovery service

35 / 50

A database system allows the following EXCEPT

management and control of data towards an efficient working of an organisation.

more critical functions in organisations to be computerised and the need to keep a large volume of data available in an up to the minute current state increased.

any user to access all its data.

integration of data across multiple applications into a single application

36 / 50

Which of the following is a correct way to implement one-to-many relationship while designing tables?

by splitting the data into two tables with primary key and foreign key relationships.

as a single table and rarely as two tables with primary and foreign key relationships.

by splitting each table into three

using a junction table with the keys from both the tables forming the composite primary key of the junction table.

37 / 50

A collection of concepts that can be used to describe the structure of a database

Data model

DBMS

Database

Data

38 / 50

Which of the following is correct?

The FD3 violates 3NF.

The relation Interview is in 3NF

The FD2 violates 2NF.

The relation Interview is in BCNF.

39 / 50

A collection of concepts that can be used to describe the structure of a database

Data model

Database

DBMS

Data

40 / 50

Which of the following most certainly implies the need for an entire table to implement?

An identifying relationship

A ternary relationship

A recursive relationship

A binary relationship

41 / 50

Consider the relation Interview (CandidateNo, InterviewDate, InterviewTime, StaffNo, RoomNo) and the following functional dependencies.
FD1 : CandidateNo, InterviewDate -> InterviewTime, StaffNo, RoomNo
FD2 : RoomNo, InterviewDate, InterviewTime -> StaffNo, CandidateNo
FD3 : StaffNo, InterviewDate -> RoomNo
Which of the following is correct?

The relation Interview is in 3NF

The FD2 violates 2NF.

The FD3 violates 3NF.

The relation Interview is in BCNF.

42 / 50

As part of database naming conventions, attribute names should use suffixes such as ID, NUMBER or CODE for the _______.

determinant

primary key

index

foreign key

43 / 50

Which of the following is a feature of PRIMARY KEY constraint?

enforces that the column will only accept null values.

limit the values that can be placed in a column.

unique identifier for a row within a database table.

allow any actions that would destroy links between tables

44 / 50

Which of the following enforces a relation into 1st normal form?

Every non-key attribute is partially dependent on super key

The domain of attribute must include only atomic values.

non-key attribute is non-transitively dependent on primary key.

Every non-key attribute is fully functionally dependent on primary key

45 / 50

Identify the constraint that limits the values that can be placed in a column.

UNIQUE

CHECK

NOT NULL

FOREIGN KEY

46 / 50

User rights information is stored in

Physical database

Logical database

Buffer

Catalog

47 / 50

Identify the correct statement.

Entity integrity constraints are specified on individual relations.

Entity integrity constraints specify that primary key values can be composite.

Entity integrity constraints are specified between weak entities.

When entity integrity rules are enforced, a tuple in one relation that refers to another relation must refer to an existing tuple.

48 / 50

Which of the following is INCORRECT with respect to file systems?

Some physical organisations use pointers to record blocks to locate records on disk.

A logical record is concerned with efficient storage of information in the secondary storage devices.

At the physical level, pointer or hashed address scheme may be employed to provide a certain degree of data independence at the user level.

The efficiency of a file system depends on how efficiently operations such as retrieve, insert, update, delete may be performed on the information stored in the file.

49 / 50

Identify the correct statement.

Entity integrity constraints are specified on individual relations.

When entity integrity rules are enforced, a tuple in one relation that refers to another relation must refer to an existing tuple.

Entity integrity constraints specify that primary key values can be composite.

Entity integrity constraints are specified between weak entities.

50 / 50

The ER- data model is an example of:

Relational database

Conceptual database

Physical database

Logical database

Your score is

The average score is 22%