Chapter 4 Multiple Choice

In a M:N relationship between STUDENT and CLASS at a university, it is possible that a class may start with no students and a student may start with no classes. If a database designer is using the O symbol using the Chen model, what is the designer hoping to establish between these entities?

An optional relationship

Starting with the objects PROFESSOR, CLASS, ROOM, how would a database begin building a diagram showcasing their relationship between each other?

Create a binary relationship

There is a CLASS entity where the first attribute CLASS_CODE is used as its entity identifier. The other attributes are CRS_CODE, CLASS_SECTION, CLASS_TIME, ROOM_CODE, PROF_NUM. If a designer would like to include an alternate composite primary key in case CLASS_CODE is deleted, what would be the most appropriate composite primary key?

CRS_CODE and CLASS_SECTION

When examining an associative entity with a primary key and two foreign keys, what can a database designer review as well to better understand the overall design?

two parent entities

When creating a strong relationship between COURSE and CLASS, which of the following would be true about the CLASS object?

It has a primary key that is also the primary key of COURSE

A large entity relationship model (ERM) diagram was presented to management but the relationships between each entity was hard to understand visually, especially with dashed lines. If using the Crow's Foot model to depict the relationships, what other actions could be done to the ERM to make it more understandable in terms of number of occurrences in the related entities?

Notate the cardinality next to each table.

After building a database using an implementation-oriented approach, the database designers must now conceptualize the model so that it appeals well to management. How should the designers conceptualize the linked attributes to a single entity?

SOLID LINE

After looking at the database design, another designer found that the primary keys were not established with a simple underline. Knowing that single-valued attribute can almost always be labeled as primary identities, which of the following attributes would be a good candidate as a primary key for a table?

SS Number

In a COURSE and CLASS relationship if the CLASS object is given a cardinality of (0,N) then which of the following would be true?

a CLASS is optional

In a PROFESSOR and COURSE relationship if the PROFESSOR object is given a cardinality of (1,1), then which of the following would be a true statement about the university?

a COURSE must have at least one PROFESSOR to teach

What is connectivity classification

classification include 1:1, 1:M, and M:N. This will help better express the relationship

What does it mean to have a strong relationship

exists when the primary key of the related entity contains a primary key component of the parent entity

A database design can deviate from normal standards when the database size is less than 100 MB.

false

A weak relationship exists if the primary key of the related entity contains at least one primary key component of the parent entity

false

In implementation terms, an entity is existence-dependent if it has a mandatory primary key.

false

What are entities represented by in the Chen model

rectangles

If a STUDENT entity is related to a bridge entity called ENROLL, and that bridge entity also included an ENROLL_GRADE attribute that is related to another parent entity called CLASS, what would the STUDENT cardinality be?

1:1

When explaining tables such as STUDENT, CLASS, or TEACHER to management as entities, they seem to not grasp the reason for each. What other term would be most acceptable to call these entities so that leadership can understand the reason for their existence in the overall database design?

OBJECT (the term entity and object are used interchangeably)

When a database designer determines that two entities share the same primary keys in their relationship, what can the designer infer between the two?

Strong relationship

Connectivities and cardinalities are established by concise statements know as business rules

TRUE

A user gets an error when entering new information into a table. The error suggests the wrong values are entered in. What can the user review about the table attributes to ensure the right values are entered in?

The attribute's domain

How are derived attributes shown in the Chen model

With a dashed line

In the relationship where "PROFESSOR teaches CLASS" and a class can have only one professor teaching, how is the PROFESSOR cardinality notated if PROFESSOR is mandatory?

1 to 1

Software vendors appreciate a database model that is implementation oriented. If a conceptual design is not idea, what characteristics of a good model would be better than web of ideas type of layout

A CROW'S FOOD ATTRIBUTE which is a compact table with associated entity and attributes

When looking at the tables, external database reviewers are unable to quickly see the derived attributes for each table as part of their normal review process. What could the CompanY internal database administrators provide to the reviewers for proper examination?

A Chen model of the database.

25. The marketing team is not able to distinguish customers in a specific city because the CUSTOMER table is too compact. The table attributes must be broken down to makethe customer city a group able query. Which of the following attributes should be simplified to improve queries for the CUSTOMER table?

ADDRESS

What is a composite attribute

An attribute that can be split apart to reveal additional results

In the early development stage, if a company suggests entities CUSTOMER and MAINTENANCE to a database designer to build a database that will track car repairs, what other entities would a designer want to add to improve the overall design based on operational needs?

CAR and PART

If CUSTOMER and INVOICE is classified as a 1:M and one direction would specify that a CUSTOMER may generate many INVOICEs, what would be true of the opposite direction?

Each INVOICE is generated by one CUSTOMER

The entity relationship model (ERM) is dependent on database type

FALSE, ERM is independent of database type

The crow's foot notation is less implementation-oriented than the Chen notation

FALSE, crows foot notation has a more implementation-oriented approach

In Chen notation, there is no way to represent cardinality

FASLE

When reading the database diagram with entities, management has a hard time understanding the implementation of these tables with just solid lines. Their relationships are still questionable. Using the tables ROOM and BUILDING, what is the most appropriate way a database designer can conceptualize their implementation in the diagram?

Insert the phrase "located in" in between

When a student's grade point average (GPA) attribute has a domain of (0,4) the GPA can hold _______ possible values

MANY

What is the logical design of databases?

Relational models

Although not required to capture, the EMPLOYEE table can have duplicates with the attributes EMPLOYEE_NUM and EMP_SPOUSE when employees marry each other. How would the database be designed better?

Removing the EMP_SPOUSE attribute.

When designing a database for a car shop, the CAR entity was first conceptualized with a few basic, common characteristics for a car like, model, make, and color. However, a car does not only have one color. If a database designer splits the COLOR attribute in a Crow's Foot model, why would this be preferred over keeping it as is?

The table cannot recognize multivalued attributes. Crow's Foot notation dosen't identify multivalued attributes

A database designer set the CRS_CODE attribute as the primary key to the CLASS table. If no other changes are made, how many composite identifiers does the table have?

ZERO

What does implementation do?

conceptualizes how the database is designed in comparison to how the organization or company operates.

If a weak relationship is required between COURSE and CLASS, then the CLASS object must have which of the following?

one foreign key and one primary key

If the entity COURSE is related to the entity CLASS, then it is only necessary to determine the connectivity from COURSE to CLASS

False Course and class could also have other entities that they are connected to

Attribute examples such as STU_NAME, STU_FNAME, and ROM_NUMBER could apply to one entity

NOPE FALSE, because rom_number would apply to class entity

Management wants to see a database design that is logical in nature. It must be easy to identify where and how each table is related to one another. How can a database designer achieve this design concept before the next meeting?

Build a relational model