Chapter 1 - Database and Technology Foundations

Abstract

One common component of most of the occurrences of information technology, such as client-server computing, business intelligence and data warehousing, packaged software for enterprise applications, call center management, and sales force automation is relational database technology with Database Management System (DBMS) products based on SQL. This chapter introduces the concepts of a database and of a database management system, as well as discusses some of the principal characteristics of database and DBMS's. A database is a collection of data, usually pertaining to some reasonably well-defined purpose. A DBMS is a special computer program built to store data into, retrieve data from, and modify data stored in a database. In general, DBMS's require that the user (some user, at least) define the format of the data very specifically. At a minimum, it requires that the user define the number of data items, the data types of those items, and how the items are related to one another. One of the most significant advantages of a DBMS is that it protects the data from many types of ill-formed operations. The chapter also describes the fundamental characteristics of database languages. These languages were designed to allow application programmers to express their computational requirements efficiently. In the end, the chapter emphasizes the point that understanding the relational model is very important given that database built upon the foundations of that model dominate the information systems world today, and SQL is the dominant language for the relational model.