các từ viết tắt của SQL vẫn còn, nhưng tên ngôn ngữ đã biến thành Structured Query Language. Sự thay đổi tên là khả năng kết quả của quay tiếp thị cấu trúc chương trình là câu thần chú trong ngày, và mặc dù SQL có gì để làm với lập trình, cấu trúc hay cách khác, bất cứ điều gì với từ cấu trúc tiêu đề của nó có sự chú ý nhiều hơn trên thị trường. | This page intentionally left blank. CHAPTER o The Database Life Cycle Before we delve into the particulars of database design it is useful to understand the framework in which the design takes place. The life cycle of a database or computer system is the term we use for all the events that take place between the time we first recognize a need for a database continuing through its development and deployment and finally ending with the day it is retired from service. Most businesses that develop computer systems have a formal process they follow. The process ensures that development runs smoothly is cost effective and that the outcome is a complete computer system that meets expectations. Databases are never designed and implemented in a vacuum there are always other components of the complete system such as the user interface application programs and reports that are developed along with the database. All the work to be accomplished over the long term is typically divided into projects with each project having its own finite list of goals sometimes called deliverables an expected timeframe for completion and a project manager or leader who will be held accountable for delivery of the project. In order to understand the database life cycle you must also understand Copyright 2004 by The McGraw-Hill Companies. Click here for terms of use. Databases Demystified the life cycle of the entire systems-development effort and the way projects are organized and managed. In this chapter we take a look at both traditional and nontradi-tional systems-development processes. Not all databases are built by businesses using formal projects and funding. However the disciplines outlined in this chapter can assist you in thinking through your database project asking the tough questions before you embark on an extended effort. The Traditional Method The traditional method for developing computer systems follows a process called the system development life cycle SDLC which divides the .
