13th Edition

ISBN: 9780134773650

Author: Hoffer

Publisher: PEARSON

Concept explainers

The enhanced ER model is an abbreviation for Enhanced Entity-Relationship (EER) model. As you know, the entity-relationship (ER) model is a pictorial illustration of the relationship between various entities of a domain. In the case of a large amount of …

Videos

Textbook Question

Chapter 2, Problem 2.23PAE

A cellular operator needs a database to keep track of its customers, their subscription plans, and the handsets (mobile phones) that they are using. The E-R diagram in Figure 2-24 illustrates the key entities of interest to the operator and the relationships between them. Based on the figure, answer the following questions and explain the rationale for your response. For each question, identify the element(s) in the E-R diagram that you used to determine your answer.

Can a customer have an unlimited number of plans?
Can a customer exist without a plan?
Is it possible to create a plan without knowing who the customer is?
Does the operator want to limit the types of handsets that can be linked to a specific plan type?
Is it possible to maintain data regarding a handset without connecting it to a plan?
Can a handset be associated with multiple plans?
Assume a handset type exists that can utilize multiple operating systems. Could this situation be accommodated within the model included in Figure 2-24?
Is the company able to track a manufacturer without maintaining information about its handsets?
Can the same operating system be used on multiple handset types?
There are two relationships between Customer and Plan. Explain how they differ.
Characterize the degree and the cardinalities of the relationship that connects Customer to itself. Explain its meaning.
Is it possible to link a handset to a specific customer in a plan with multiple customers?
Can the company track a handset without identifying its operating system?

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Chapter 2, Problem 2.22RQ

Chapter 2, Problem 2.24PAE

Students have asked these similar questions

Please original work What are four of the goals of information lifecycle management think they are most important to data warehousing, Why do you feel this way, how dashboards can be used in the process, and provide a real life example for each. Please cite in text references and add weblinks

The following is code for a disc golf program written in C++: // player.h #ifndef PLAYER_H #define PLAYER_H #include <string> #include <iostream> class Player { private: std::string courses[20]; // Array of course names int scores[20]; // Array of scores int gameCount; // Number of games played public: Player(); // Constructor void CheckGame(int playerId, const std::string& courseName, int gameScore); void ReportPlayer(int playerId) const; }; #endif // PLAYER_H // player.cpp #include "player.h" #include <iomanip> Player::Player() : gameCount(0) {} void Player::CheckGame(int playerId, const std::string& courseName, int gameScore) { for (int i = 0; i < gameCount; ++i) { if (courses[i] == courseName) { // If course has been played, then check for minimum score if (gameScore < scores[i]) { scores[i] = gameScore; // Update to new minimum…

In this assignment, you will implement a multi-threaded program (using C/C++) that will check for Prime Numbers and Palindrome Numbers in a range of numbers. Palindrome numbers are numbers that their decimal representation can be read from left to right and from right to left (e.g. 12321, 5995, 1234321). The program will create T worker threads to check for prime and palindrome numbers in the given range (T will be passed to the program with the Linux command line). Each of the threads works on a part of the numbers within the range. Your program should have some global shared variables: • numOfPrimes: which will track the total number of prime numbers found by all threads. numOfPalindroms: which will track the total number of palindrome numbers found by all threads. numOfPalindromic Primes: which will count the numbers that are BOTH prime and palindrome found by all threads. TotalNums: which will count all the processed numbers in the range. In addition, you need to have arrays…

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. 2.4RQ Ch. 2 - Prob. 2.5RQ Ch. 2 - Prob. 2.6RQ Ch. 2 - State six general guidelines for naming data...Ch. 2 - Prob. 2.8RQ Ch. 2 - Prob. 2.9RQ Ch. 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. 2.18RQ Ch. 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. 2.24PAE Ch. 2 - Answer the following questions concerning Figure...Ch. 2 - Prob. 2.26PAE Ch. 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. 2.29PAE Ch. 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. 2.33PAE Ch. 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. 2.37PAE Ch. 2 - Review Figure 2-8LQ and Figure 2-22. Identify any...Ch. 2 - Prob. 2.39PAE Ch. 2 - Prob. 2.40PAE Ch. 2 - Prob. 2.41PAE Ch. 2 - Prob. 2.42PAE Ch. 2 - Prob. 2.43PAE Ch. 2 - Prob. 2.44PAE Ch. 2 - Prob. 2.45PAE Ch. 2 - Prob. 2.46PAE Ch. 2 - Prob. 2.47PAE Ch. 2 - Prob. 2.48PAE Ch. 2 - Draw an ERD for the following situation. (State...Ch. 2 - Prob. 2.50PAE Ch. 2 - Prob. 2.51PAE Ch. 2 - Review your answer to Problem and Exercise 2-49 if...

Additional Engineering Textbook Solutions

Find more solutions based on key concepts

A nozzle at A discharges water with an initial velocity of 36 ft/s at an angle with the horizontal. Determine ...

Vector Mechanics For Engineers

Why is the study of database technology important?

Database Concepts (8th Edition)

17–1C A high-speed aircraft is cruising in still air. How does the temperature of air at the nose of the aircra...

Thermodynamics: An Engineering Approach

What is the importance of modeling in engineering? How are the mathematical models for engineering processes pr...

HEAT+MASS TRANSFER:FUND.+APPL.

How does a computers main memory differ from its auxiliary memory?

Java: An Introduction to Problem Solving and Programming (8th Edition)

What is an uninitialized variable?

Starting Out with Programming Logic and Design (5th Edition) (What's New in Computer Science)

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.