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Chapter 7: Problem 16

Consider a library application that needs to keep track of books that have been borrowed. Suppose there is an entity type Loan that has attributes bookID, memberID, dateBorrowed and dateDue. Suppose the due date is always 2 weeks after the borrowed date. Show Loan and its attributes in an ERD.

Short Answer

Expert verified
The 'Loan' entity contains the attributes 'bookID', 'memberID', 'dateBorrowed', 'dateDue'. The ER Diagram consists of a rectangle for the 'Loan' entity and the related attributes are connected to the entity by lines.

Step by step solution

01

Understand the Problem

Interpret the problem and ascertain the requirements. This is a library system where books can be borrowed. It needs to track all the loaned books. For each loan, it needs to record the bookID, memberID, date the book was borrowed, and the due date, which is two weeks after the borrowing date.
02

Identify Entities and Attributes

In this problem, we have only one entity, that is 'Loan'. Attributes for this entity include 'bookID', 'memberID', 'dateBorrowed' and 'dateDue'. Each attribute stores significant data related to the loan entity.
03

Drawing the ER Diagram

Start by drawing a rectangle representing the 'Loan' entity. Vertically list the attributes: 'bookID', 'memberID', 'dateBorrowed', 'dateDue' in ovals, connected to the 'Loan' entity rectangle by lines.

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Most popular questions from this chapter

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