计算机外文翻译---数据库开发过程(编辑修改稿)

计算机外文翻译---数据库开发过程(编辑修改稿)内容摘要：

ween the concept of modeling data in both systems development life cycle stages between. Modeling Database development process from the enterprise modeling (system development life cycle stage of the project feasibility studies, and to choose a part) Organizations set the scope and general database content. Enterprise modeling in information systems planning and other activities, these activities determine which part of information systems need to change and strengthen the entire organization and outlines the scope of data. In this step, check the current database and information systems, development of the project as the main areas of the nature of the business, with a very general description of each term in the development of information systems when needed data. Each item only when it achieved the expected goals of organizations can be when the next step. Data Modeling One has already begun on the Information System project, the concept of data modeling phase of the information systems needs of all the data. It is divided into two stages. First, it began the project in the planning stage. At the same time outlining the establishment of other documents to the existing database without considering the circumstances specific development projects in the scope of the required data. This category only includes highlevel data (entities), and main contact. Then in the system development lifecycle analysis stage must have a management information system set the entire organization Details of the data model definition of all data attributes, listing all data types that all data interentity business linkages, defining description of the full data integrity rules. In the analysis phase, but also the concept of inspection data model (also called the concept behind the model) and the goal of information systems used to explain other aspects of the model of consistency categories, such as processing steps, rules and data processing time of timing. However, even if the concept is such detailed data model is only preliminary, because followup information system life cycle activities in the design of services, statements, display and inquiries may find that missing element or mistakes. Therefore, the concept of data often said that modeling is a topdown manner, its areas of operation from the general understanding of the driver, rather than the specific information processing activities by the driver. 3. Logical Database Design Logical database design from two perspectives database development. First, the concept of data model transform into relational database theory based on the criteria that means between. Then, as the design of information systems, every puter procedures (including procedures for the input and output format), database support services, statements, and inquiries revealed that a detailed examination. In this socalled Bottomup analysis, accurate verification of the need to maintain the database and the data in each affairs, statements and so on the needs of those in the nature of the data. For each separate statements, services, and so on the analysis must take into account a specific, limited but plete database view. When statements, services, and other analysis might be necessary to change the concept of data model. Especially in largescale projects, the different analytical systems development staff and the team can work independently in different procedures or in a centralized, the details of their work until all the logic design stage may be displayed. In these circumstances, logic database。