Databases: more than a bunch of numbers

Information systems consist of 4 functional layers: 1. the specific functionality placed by a programmer into screens, menus, and reports, 2. the tools and facilities provided to create applications, 3. the data management functionality, and 4. the actual data. The value of database systems lies in their ability to manage these 4 layers separately. An organization should consider 5 major issues in deciding whether or not to manage data separately from their use in applications: 1. structure, 2. integrity, 3. data sharing, 4. confidentiality, and 5. data life cycle. The need for unencumbered access to information has made end-user reporting a key issue for the information system industry. Software vendors have developed 4 broad categories of products: 1. programmers' report-writing tools, 2. database connect tools, 3. business views, and 4. natural language. Managing the layers of information system architecture separately allows users to make the most of the firm's investment in database system development.