Modern Database Management
13th Edition
ISBN: 9780134773650
Author: Hoffer
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 2, Problem 2.10RQ
State three conditions that suggest the designer should model a relationship as an associative entity type.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
What is a strong entity type?
Examine the following entity relationship diagram, and select all statements that correctly describe this diagram.
PHOTOGRAPHER
PK PHOTOGRAPHER ID
FIRST_NAME
LAST_NAME
++
uses
PK
+PK,FK1
CAMERA
MODEL NR
PHOTOGRAPHER ID
DESCRIPTION
a. The CAMERA entity has a composite primary key.
Ob. The existence of each CAMERA instance depends upon the existence of a PHOTOGRAPHER instance.
c. Each CAMERA instance is associated with exactly one PHOTOGRAPHER instance.
d. A PHOTOGRAPHER uses one or more CAMERAS.
e. Both PHOTOGRAPHER and CAMERA are strong entities.
Where do object-oriented and entity-relationship models diverge in terms of the idea of an object?
Chapter 2 Solutions
Modern Database Management
Ch. 2 - Define each of the following terms: entity type...Ch. 2 - Match the following terms and definitions....Ch. 2 - Contrast the following terms: stored attribute;...Ch. 2 - Prob. 2.4RQCh. 2 - Prob. 2.5RQCh. 2 - Prob. 2.6RQCh. 2 - State six general guidelines for naming data...Ch. 2 - Prob. 2.8RQCh. 2 - Prob. 2.9RQCh. 2 - State three conditions that suggest the designer...
Ch. 2 - List the four types of cardinality constraints,...Ch. 2 - Give an example, Other than those described in...Ch. 2 - What is the degree of a relationship? List the...Ch. 2 - Give an example (Other than those described in...Ch. 2 - Give an example of each of the following, other...Ch. 2 - Give an example of the use of effective (or...Ch. 2 - State a rule that says when to extract an...Ch. 2 - Prob. 2.18RQCh. 2 - In addition to explaining what action is being...Ch. 2 - For the Manages relationship in Figure 2-12a,...Ch. 2 - Explain the distinction between entity type and...Ch. 2 - Why is it recommended that every ternary...Ch. 2 - A cellular operator needs a database to keep track...Ch. 2 - Prob. 2.24PAECh. 2 - Answer the following questions concerning Figure...Ch. 2 - Prob. 2.26PAECh. 2 - You may have been assigned a CASE or a drawing...Ch. 2 - Consider the two E-R diagrams in Figure 2-25 Q,...Ch. 2 - Prob. 2.29PAECh. 2 - Are associative entities also weak entities? Why...Ch. 2 - Because Visio does not explicitly show associative...Ch. 2 - Figure 2-26 shows a grade report that is mailed to...Ch. 2 - Prob. 2.33PAECh. 2 - The Is Married To relationship in Figure 2-12a...Ch. 2 - Figure 2-27 represents a situation of students who...Ch. 2 - Figure 2-28 shows two diagrams (A and B), both of...Ch. 2 - Prob. 2.37PAECh. 2 - Review Figure 2-8LQ and Figure 2-22. Identify any...Ch. 2 - Prob. 2.39PAECh. 2 - Prob. 2.40PAECh. 2 - Prob. 2.41PAECh. 2 - Prob. 2.42PAECh. 2 - Prob. 2.43PAECh. 2 - Prob. 2.44PAECh. 2 - Prob. 2.45PAECh. 2 - Prob. 2.46PAECh. 2 - Prob. 2.47PAECh. 2 - Prob. 2.48PAECh. 2 - Draw an ERD for the following situation. (State...Ch. 2 - Prob. 2.50PAECh. 2 - Prob. 2.51PAECh. 2 - Review your answer to Problem and Exercise 2-49 if...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.Similar questions
- Create an Entity-Relationship model for the following descriptions: Doctors, nurses, and patients have the following unique numbers respectively: doctorNo, nurseNo, and patientNo.arrow_forwardDraw the EER diagram keeping in mind the condtitions.arrow_forwardIn a descriptive model, what are the primary elements that make up the structure?arrow_forward
- Draw an Entity Relationship Diagram for the following scenario A, B, and C are entities. There is a relationship between all three, called D. For each A and B there is one C. For each B and C there can be many A’s. For each A and C, there is one B. Every time the relationship, D, is satisfied, a single value, “Note”, will be storedarrow_forwardEntity-Relationship Diagram (ERD) is one of the data modeling tools that provides a software engineer with the ability to represent data objects, their characteristics, and their relationships. Use an ERD to describe the following scenario. A teacher is identified by an ID number (TID), last name (LName), and first name (FName). A project is identified by a project ID (PID) and title (T). A student is identified by an ID number (SID), last name (LName), and first name (FName). A teacher can supervise zero, one, or many students and a student is supervised by one teacher. A teacher must propose one or many projects and every project is proposed by one teacher. A student must work on one project and every project is worked by only one student.arrow_forwardENHANCED CHEN METHODOLOGYEER MODEL3-25For a library, the entity type HOLDING has four sub-types: BOOK, AUDIO BOOK, DVD, and SOFTWARE. Draw a separate EER diagram segment for each of the following situations:a. At a given time, a holding must be exactly one of these subtypes.b. A holding may or may not be one of these subtypes. However, a holding that is one of these subtypes cannot at the same time be one of the other subtypes.c. A holding may or may not be one of these subtypes. On the other hand, a holding may be any two (or even four) of these subtypes at the same time.d. At a given time, a holding must be at least one of these subtypes. 3-26A bank has three types of accounts: checking, savings, and loan. Following are the attributes for each type of account:CHECKING: Acct No, Date Opened, Balance, Service ChargeSAVINGS: Acct No, Date Opened, Balance, Interest RateLOAN: Acct No, Date Opened, Balance, Interest Rate, PaymentAssume that each bank account must be a member of exactly one…arrow_forward
- SUBJECT:SOFTWARE ENGINEERING I NEED THE ANSWER QUICKLY Q3. Consider the use-case description and domain model, which shows the navigability of the associations, for the video sales and rental shop application. Using only one boundary class, one control class and any of the entity classes specified in the domain model. Write the flow of events analysis for this use case and construct a sequence diagram that shows the objects required to realize this use case and the messages that are passed among the objects. State any assumptions that you need to make. Flow of events for Reserve Video (Staff scenario) Use Case Analysis: 1. The ReserveVideo Ul object displays the screen for reserving a video. 2. The user enters the member number and the movie ID. 3. The ReserveVideoUI asks the ReserveVideoMgr to reserve the indicated video . 4. Tile ReserveVideoMgr gets the list of rental copies for the movie from the MovieVideo object. 5. The ReserveVideoMgr searches through the list of rental…arrow_forwardRelationships in a use case diagram are a powerful mechanism to organize and reuse requirements. There are three main types of relationships in use case diagrams:1.Actor to actor—This is the generalization relationship and represented by the inheritance arrow in Figure 6.1. This relationship was also discussed in the previous chapter (notably Figure 5.3).2.Actor to use case—The relationship between an actor and a use case is called an association, also occasionally called "communication" because it represents a communication between the actor and the system. This association is represented by a straight line in Figure 6.1. The association is an interface through which an actor interacts with the system. Occasionally, an association line may have an arrowhead (not shown in Figure 6.1), representing the actor initiating the use case. This direction on the association relationship is only shown if absolutely necessary.3.Use case to use case—There are three specific relationships permitted…arrow_forwardWhat distinguishes a weak entity set from a strong entity set?arrow_forward
- With examples, explain the distinctions between is-a relationship and has-a relationship.arrow_forwardDraw an entity-relationship diagram, including minimum and maximum cardinality, for the following: The system stores information about two things: cars and owners. A car has attributes for make, model, and year. The owner has attributes for name and address. Assume that a car must be owned by one owner and an owner can own many cars, but an owner might not own any cars (perhaps she just sold them all, but you still want a record of her in the system).arrow_forwardDraw a class design of a gpa calculator including Entity Classes Attributes: datatypes, accessibility Relationships Associations, Aggregations, Compositions; names, directions etc. Generalization- specializationarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Database System ConceptsComputer ScienceISBN:9780078022159Author:Abraham Silberschatz Professor, Henry F. Korth, S. SudarshanPublisher:McGraw-Hill Education
Starting Out with Python (4th Edition)Computer ScienceISBN:9780134444321Author:Tony GaddisPublisher:PEARSON
Digital Fundamentals (11th Edition)Computer ScienceISBN:9780132737968Author:Thomas L. FloydPublisher:PEARSON
C How to Program (8th Edition)Computer ScienceISBN:9780133976892Author:Paul J. Deitel, Harvey DeitelPublisher:PEARSON
Database Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781337627900Author:Carlos Coronel, Steven MorrisPublisher:Cengage Learning
Programmable Logic ControllersComputer ScienceISBN:9780073373843Author:Frank D. PetruzellaPublisher:McGraw-Hill Education
Database System Concepts
Computer Science
ISBN:9780078022159
Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:McGraw-Hill Education
Starting Out with Python (4th Edition)
Computer Science
ISBN:9780134444321
Author:Tony Gaddis
Publisher:PEARSON
Digital Fundamentals (11th Edition)
Computer Science
ISBN:9780132737968
Author:Thomas L. Floyd
Publisher:PEARSON
C How to Program (8th Edition)
Computer Science
ISBN:9780133976892
Author:Paul J. Deitel, Harvey Deitel
Publisher:PEARSON
Database Systems: Design, Implementation, & Manag...
Computer Science
ISBN:9781337627900
Author:Carlos Coronel, Steven Morris
Publisher:Cengage Learning
Programmable Logic Controllers
Computer Science
ISBN:9780073373843
Author:Frank D. Petruzella
Publisher:McGraw-Hill Education
Enhanced Entity Relationship Model; Author: Data Science Center;https://www.youtube.com/watch?v=ocQUtXPumdQ;License: Standard YouTube License, CC-BY