WorksheetsDBMS schema ER normalization
Total questions: 31
Worksheet time: 14mins
Data redundancy occurs
when the same piece of data exists in multiple places.
when there is mismatch of data.
when there is NULL values.
when there is multiple values for an attribute.
The design of a DBMS
depends on its ER diagram.
depends on its architecture.
depends on its Entity set.
depends on its attributes.
A data schema is a formal
description of relations.
description of database.
description of data.
description of tuples.
A key that can be uniquely used to identify a database record, that may contain extra attributes that are not necessary to uniquely identify records.
Foreign key.
Primary key.
Candidate key.
Super key.
Referential integrity constraint states that if a relation refers to a key attribute of a different or same relation, then that key element must exist.
TRUE.
FALSE.
Database transactions intended to guarantee data validity
despite errors or power failures.
despite data mismatch.
despite data redundancy.
despite data inconsistency.
Normalization of a Database is achieved by following a set of rules called 'forms' in creating the database.
TRUE.
FALSE.
Functional dependency X→Y.
It is denoted by X→Y.
X is called the determinant.
Y depends upon X.
All of them.
If there is only one candidate key then the 3NF and BCNF are identical .
TRUE.
FALSE.
A relation decomposed into two relations must have loss-less join Property, which ensures that no spurious or extra tuples are generated
when tuples are reunited.
when a transaction is carried out.
when relations are decomposed.
when relations are reunited through a natural join
The minimum and maximum values of connectivity is called the __________ of the relationship.
cardinality
degree
modality
tuple
When each entity in the entity set may not occur in at least one relationship in that relationship set, is called:
Partial Participation
Total Participation
Conditional Participation
Relational Participation
An entity is a
object of relation
present working model
thing in real world
model of relation
Which of the following is not a component of ER Model in DBMS?
entity
database
attribute
relationship
A relationship is
an item in an application
a meaningful dependency between entities
a collection of related entities
a related data
The expansion of ER Diagram is
Entity Relationship diagram
Entity Relative diagram
Entity Relation diagram
Entity Rationalized diagram
Entity is represented as
ellipse
double ellipse
rectangle
double rectangle
In one to many relationship, the entity that is on the one side of relationship is called
subtype
child
instance
parent
Property that describes the characteristics of entity is
entities
relationship
attributes
identifiers
Entities can be associated with one another in which of the following
attribute
identifiers
entities
relationship
By relation cardinality we mean
number of items in a relationship
number of relationships in which an entity can appear
number of items in an entity
number of entity sets which may be related to a given entity
Rows of a relation is called
a relation row
an entity
a data structure
tuples
Attributes are
properties of relationship
attributed to entities
properties of members of an entity set
The attribute AGE is calculated from DATE_OF_BIRTH. The attribute AGE is
Single valued
Multi valued
Composite
Derived
The attribute name could be structured as an attribute consisting of first name, middle initial, and last name. This type of attribute is called
Simple attribute
Composite attribute
Multivalued attribute
Derived attribute
An entity in A is associated with at most one entity in B, and an entity in B is associated with at most one entity in A.This is called as
One-to-many
One-to-one
Many-to-many
Many-to-one
Which one of the following uniquely identifies the elements in the relation?
Secondary Key
Primary key
Foreign key
Composite key
What do double line represent in an ER diagram
They link entity sets to relationship sets
Total participation of an entity in a relationship set
Relationship sets linked to weak entity sets
None of the mentioned
