【導讀】模型描述了由組織維護的數(shù)據(jù)的范圍。圖1顯示松谷家具公司的企業(yè)數(shù)。據(jù)模型的一個部分。在信息系統(tǒng)規(guī)劃期間，你可以建立一個企業(yè)數(shù)據(jù)模。型作為整個信息系統(tǒng)體系結(jié)構(gòu)的一部分。網(wǎng)絡(luò)連接和拓撲圖來顯示）。數(shù)據(jù)的發(fā)送者和接收者）。執(zhí)行過程的事件和時間點。自頂向下規(guī)劃可使開發(fā)人員更全面地規(guī)劃信息系統(tǒng)，提供一種考慮系統(tǒng)組。于從信息系統(tǒng)和技術(shù)的投資中獲取最大利益是非常重要的。關(guān)鍵性的規(guī)劃因素是指組織目標、關(guān)鍵的成功因素和問題領(lǐng)域。素的目的是建立規(guī)劃的環(huán)境并且將信息系統(tǒng)規(guī)劃與戰(zhàn)略業(yè)務(wù)規(guī)劃聯(lián)系起來。理者為新的信息系統(tǒng)和數(shù)據(jù)庫社頂優(yōu)先級以處理需求。售數(shù)據(jù)、新的市場研究數(shù)據(jù)和新產(chǎn)品的測試數(shù)據(jù)。生產(chǎn)部共同的責任）?；谛畔⒐こ痰男畔⑾到y(tǒng)規(guī)劃是數(shù)據(jù)庫開發(fā)項目的一個來源。存管理或進行更精確的銷售預測。該加到當前的組織數(shù)據(jù)資源中去。

　　

【正文】 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 design stage must be the original concept of data model and user view these independent or merged into a prehensive design. In logic design information systems also identify additional information processing needs of these new demands at this time must be integrated into the logic of earlier identified in the database design. Logical database design is based on the final step for the formation of good data specifications and determine the rules, the bination, the data after consultation specifications or converted into basic atomic element. Most of today39。s database, these rules from the relational database theory and the process known as standardization. This step is the result of management of these data have not cited any database management system for a plete description of the database map. Logical database design pleted, we began to identify in detail the logic of the puter program and maintenance, the report contents of the database for inquiries. 4. Physical database design and definition Physical database design and definition phase decisions puter memory (usually disk) database in the anization, definition of According to the library management system for physical structure, the procedures outlined processing services, produce the desired management information and decision support statements. The objective of this stage is to design an effective and safe management of all dataprocessing database, the physical database design to closely integrate the information systems of other physical aspects of the design, including procedures, puter hardware, operating systems and data munications works. 5. Database Implementation The database prepared by the realization stage, testing and installation procedures for handling databases. Designers can use the standard programming language (such as COBOL, C or Visual Basic), the dedicated database processing languages (such as SQL), or the process of the nonexclusive language programming in order to produce a statement of the fixed format, the result will be displayed, and may also include charts. In achieving stage, but also the pletion of all the database files, training users for information systems (database) user setup program. The final step is to use existing sources of information (documents legacy applications and databases and now needs new data) loading data. Loading data is often the first step in data from existing files and databases to an intermediate format (such as binary or text files) and then to turn intermediate loading data to a new database. Finally, running databases and related applications for the actual user maintenance and retrieval of data. In operation, the regular backup database and the database when damaged or affected resume database. 6. Database maintenance During the database in the progressive development of database maintenance. In this step, in order to meet changing business conditions, in order to correct the erroneous database design, database applications or processing speed increase, delete or change the structure of the database. When a procedure or failure of the puter database affect or damage the database may also be reconstruction. This step usually is the longest in the database development process step, as it continued to databases and related applications throughout the life cycle, the development of each database can be seen as a brief database development process and data modeling concepts arise, logical and physical database design and database to achieve dealing with the changes. Information System developed by other means System Development Life Cycle minor changes in law or its variant of the often used to guide information systems and database development. Information System is a lifecycle methodology, it is highly structured approach, which includes many checks and balances to ensure that every step of produce accurate results, and new or alternative information system and it must munications or data definitions consistent existing system needs consistency. System development life cycle because of the regular need to have a working system for a long time been criticized because only work in the system until the end of the whole process generated. More and more anizations now use rapid application development method, it is a includes analysis, design and implementation of steps to repeat the rapid iterative process until convergence to users the system so far. Rapid Application Development Act required the database has been in existence, and