【正文】 年 月 日 注： 請(qǐng)將該封面與附件裝訂成冊(cè)。然而許多數(shù)據(jù)庫(kù)開發(fā)項(xiàng)目更多的是以自底 向上的方式出現(xiàn)的，例如信息系統(tǒng)的用戶需要特定的信息來完成他們的工作，從而請(qǐng)求開始一個(gè)項(xiàng)目，又如其他信息系統(tǒng)的專家發(fā)現(xiàn)組織需要改進(jìn)數(shù)據(jù)管理而開始新的項(xiàng)目。然而如圖所示，這些步驟并不是純線性的，每個(gè)步驟在時(shí)間上有所重疊（因此可以并行地管理步驟），而且當(dāng)需要重新考慮先前的決 策時(shí)，還可以回滾到前面某些步驟。它分為兩個(gè)階段。 邏輯數(shù)據(jù)庫(kù)設(shè)計(jì)從兩個(gè)角度進(jìn)行數(shù)據(jù)庫(kù)開發(fā)。在進(jìn)行邏輯信息系統(tǒng)設(shè)計(jì)時(shí)也可以確定額外的信息處理需求，此時(shí)這些新的需求必須集成到前面確定的邏輯數(shù)據(jù)庫(kù)設(shè)計(jì)中。設(shè)計(jì)人員可以使用標(biāo)準(zhǔn)的編程語言（如 COBOL、 C 或 Visual Basic）、專用的數(shù)據(jù)庫(kù)處理語言（如 SQL），或?qū)Ｓ玫姆沁^程化語言來編程，以產(chǎn)生固定格式的報(bào)表、顯示結(jié)果，可能還包括圖表。當(dāng)一個(gè)程序或計(jì)算機(jī)發(fā)生故障而使數(shù)據(jù)庫(kù)受到影響或損壞時(shí)也可能應(yīng)該重建數(shù)據(jù)庫(kù)。原型法是一個(gè)系統(tǒng)開發(fā)的迭代過程，通過分析員和用戶的緊密配合，持續(xù)地修改系統(tǒng)而最終將所有需求轉(zhuǎn)換成一個(gè)工作系統(tǒng)。而且文檔管理也延遲到項(xiàng)目的最后，在交付使用時(shí) 才進(jìn)行用戶培訓(xùn)。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 organization, 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 ot