IT 214

Entity _ in a relationship expresses the minimum and maximum numbers of entity instances occurrences associated with one entity instant occurrence of the related entity

Cardinality

A _ attribute is an attribute that contains two values for two entity instances

Composite

A blank attribute is an activity that can be divided in simpler parts that have different somatic meanings in the real world

Composite

A relationship _ indicates a number of entities or participants associated with a relationship.

DEGREE

The _ (set of values) of an attribute may represent an entity itself (e.g. an address of a person, a city in which a person is living, the phone number of a person).

Domain

A _ attribute is an atribute that may have the same value for two entity instances (already defined or to be defined in the future).

Duplicated

A _ attribute is an attribute that may have to entity instances

Duplicated

A _ has a distinct existence as an individual unit

Entity

Which of the following types of attributes has two or more values for some entity instance

Multi-valued

An album has a name Does this specification represent a relationship?

No

A many to one relationship between entities E1 and E2, one entity instance of E1 may be in a relationship with at most one entity instance of E2

RIGHT

I consist of raw facts, qualitative or quantitative characteristics of an entity.

RIGHT

In a many to one relationship between entities E1 and E2, one entity instance of E2 may be in a relationship with none, one or many entity instances of E1.

RIGHT

A _ attribute is an attribute that must have a value for all entity instances (already define or to be defined in the future)

Right

A multi-value attribute has two or more values for some entity instance

Right

A relationship degree indicates a number of entities or participants associated with a relationship

Right

A relationship degree indicates a number of entities or participants associated with a relationship.

Right

A strong relationship is also known as identifying relationship

Right

A week relationship is also known as a non-identifying relationship.

Right

An entity is a thing that exists either physically or logically.

Right

An optional attribute is an attribute that may not have a value for some entity instance (already defined or to be defined in the future)

Right

Attributes are properties of entities

Right

For naming entities, find a specific name that covers all possible data currently stored or to be stored in the future.

Right

In a one to many relationship between entities E1 and E2, one entity instance of E1 may be in relationship with none, one or many entity instances of E2

Right

Knowledge is the awareness and understanding of some thing (EG entity) based on the information required about it

Right

The entity person the attribute names and example of a composite attribute

Right

The relational model represents Data in tuples grouped in relations. A tuple contains the values for related attributes (i.e. columns) from a predefined datatype (i.e. domain). When the relation is shown as a table, the tuples are the rows and attributes of the columns. in design, the relationship corresponds to an entity and the tuples to entity instances.

Right

for the entity person the attribute address is an example of a composite attribute

Right

in a one to one relationship between entities E1 and E2, one entity instance of E1 may be in a relationship with at most one entity instance of E2.

Right

For the entity person, which of the following attributes can be used as a primary key?

SSN

An _ attribute is an attribute that cannot be divided in simpler parts that has a different Semitic meaning in the real world

Simple

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

Unary

A _attribute is an attribute that has a unique (different) value or no value at all for all entities instances (already defined or to be defined in the future)

Unique

an attribute that has a different value or no value at all for all entity instances already define or to be defined in the future is named.

Unique value

Given a multi-value attribute, with a variable number of values, for which we need to process independently the values, it is not recommended to consider a new dependent entity to represent the values.

WRONG

In an entity that has only candidates keys with four or more attributes, it is not recommended to create a surrogate key for the entity.

WRONG - It is recommended

A database is defined as any data stored and access on a computer system.

WRONG- generally it is

In an entity with a set of related attributes describing one of his characteristics, having a lot of duplicated to tuples that must be fied together, risking data anomalies. For instance, for games in a soccer tournament it is stored the address of the field where the game will take place. In this situation it is not recommended to consider a new entity describing these attributes.

WRONG- this situation it is recommended to consider a new entity describing these attributes, to allow global updates and avoid data anomalies

Crows foot notation depicts a _ relationship by placing a dashed line between the entities.

Weak

In a _ relationship, the PK of the related (child) entity does not contain a PK component of the parent entity.

Weak

A binary relationship exist when two entities are associated.

Wrong

A primary key is a field(or collection of fields) in one table that uniquely identifies a row of another table

Wrong

A relationship in the ER model represents a general real or abstract concept or entity?

Wrong

For the entity person the attribute address is an example of a simple attribute

Wrong

I'm naming entities if the name uses multiple words, separate them by a semicolon.

Wrong

In a many to many relationship between entities E1 and E2, one entity instance of E1 may be in a relationship with at most one entity instance of E2

Wrong

In a many to one relationship between entities E1 and E2, one entity instance of E1 may be in a relationship with none, one or many entity instances of E2

Wrong

In a one to one relationship between entities E1 and E2, one entity instant see one may be in a relationship with none, one or many entity instances of E2

Wrong

RD is the notation for a relational database.

Wrong

Reviews are named with verb phrases describing an entity.

Wrong

The optional attribute is an attribute that has no value for at least one entity and instance already defined

Wrong

The term "cardinality" for a relationship expresses the number of entities associated by the relationship.

Wrong

crow's foot notation depicts the strong (identifying) relationship with a "dashed" line between the entities.

Wrong

while naming entities if the name uses multiple words, separate them by a semicolon

Wrong

"A professor teaches a class" is not a good relationship name

Wrong - it is

'Aircraft is flown by a crew' is not a good name for a relationship

Wrong - it is

specification: a student has many advisers and an advisor any students. The above specifications indicates a relationship between student and advisor having the type:

many-to-many

A _ attribute is an attribute that may have a value for some entity instances (already defined or to be defined in the future).

optional

the __ model represents data tuples grouped in relations.

relational

A _ in ER model represents an association among entities

relationship

Relationships in ER models are usually written in lowercase

right

crow's foot notation depicts the strong (identifying) relationship with a 'solid' lie between the entities.

right

strong relationships exist when the PK of the child entity contains the PK of the parent entity.

right

A _ attribute is naturally that must have a value for all entity instances.

single

an entity is a:

thing in real or conceptual world

A _ relationship exist when an association is maintained within a single entity

unary

In a database keeping the history of sold cars in a county, for the entity car, the attribute price is not an example of a required attribute

wrong

Relationship in ER model are usually written in upper cases.

wrong

The primary key is a field (or collection of fields) in one table that uniquely identifies a row of another table

wrong

in a one to one relationship between entities E1 and E2, one entity instance of E1 may be in a relationship with at most one entity instance of E2

wrong

many to one relationship between entities E1 and E2, one entity instance of the one may be in a relationship with none, one or many entity instances of E2

wrong

An album contains one or more tracks. Does the specification represent a relationship?

yes