Accounting information system an overview 9e bodnar and hopwood 2015 chapter 17

Database Design Using the REA Data Model Chapter 17 Copyright © 2015 Pearson Education, Inc 17-1 Learning Objectives • Discuss the steps for designing and implementing a database system • Use the REA data model to design an AIS database • Draw an REA diagram of an AIS database • Read an REA diagram and explain what it reveals about the business activities and policies of the organization being modeled Copyright © 2015 Pearson Education, Inc 17-2 Database Design Process Copyright © 2015 Pearson Education, Inc 17-3 Data Modeling • Process of defining a database so that it faithfully represents all aspects of the organization, including its interactions with the external environment ▫ Entity-relationship (E-R) diagrams ▫ REA data model Copyright © 2015 Pearson Education, Inc 17-4 REA Modeling • Resources ▫ Things that have economic value to the organization (e.g., inventory, cash) • Events ▫ Various business activities that management wants to collect information on • Agents ▫ People and organizations that participate in events (both internal (e.g., employees) and external (e.g., customers/vendors) to the organization) Copyright © 2015 Pearson Education, Inc 17-5 REA Basic Template Copyright © 2015 Pearson Education, Inc 17-6 Creating an REA Model • Identify relevant events ▫ Give-get exchange (economic duality) • Identify resources and agents ▫ Resource reduced in give event ▫ Resource acquired in get event • Determine cardinalities of relationships ▫ Nature of the relationship between the two entities Copyright © 2015 Pearson Education, Inc 17-7 Cardinality Notation Methods • Graphical symbols ▫ Graphical symbols represent minimum– maximum cardinalities • (Min, Max) notation ▫ Pairs representing the minimum–maximum cardinalities • UML notation ▫ Pairs representing the minimum–maximum cardinalities • Maximums only (Microsoft Access) Copyright © 2015 Pearson Education, Inc 17-8 Key Terms • Data modeling • Entity-relationship (E-R) diagram • REA data model • Resources • Events • Agents • Cardinalities Copyright © 2015 Pearson Education, Inc • • • • Minimum cardinality Maximum cardinality One-to-One (1:1) relationship One-to-Many (1:N) relationship • Many-Many (M:N) relationship ... the steps for designing and implementing a database system • Use the REA data model to design an AIS database • Draw an REA diagram of an AIS database • Read an REA diagram and explain what it reveals... employees) and external (e.g., customers/vendors) to the organization) Copyright © 2015 Pearson Education, Inc 17- 5 REA Basic Template Copyright © 2015 Pearson Education, Inc 17- 6 Creating an REA... economic value to the organization (e.g., inventory, cash) • Events ▫ Various business activities that management wants to collect information on • Agents ▫ People and organizations that participate