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計(jì)算機(jī)外文翻譯---數(shù)據(jù)庫開發(fā)過程-在線瀏覽

2024-07-23 17:25本頁面
  

【正文】 展。當(dāng)一個(gè)程序或計(jì)算機(jī)發(fā)生故障而使數(shù)據(jù)庫受到影響或損壞時(shí)也可能應(yīng)該重建數(shù)據(jù)庫。 信息系統(tǒng)開發(fā)的其他方法 系統(tǒng)開發(fā)生命周期法或其稍作變化的變體經(jīng)常用于指導(dǎo)信息系統(tǒng)和數(shù)據(jù)庫的開發(fā)。系統(tǒng)開發(fā)生命周期法經(jīng)常由于產(chǎn)生一個(gè)工作系統(tǒng)需要很長的 時(shí)間而受到批評(píng),因?yàn)楣ぷ飨到y(tǒng)僅僅在整個(gè)過程結(jié)束時(shí)才產(chǎn)生??焖賾?yīng)用開發(fā)法在所需的數(shù)據(jù)庫已經(jīng)存在、增強(qiáng)系統(tǒng)主要是為了檢索數(shù)據(jù)的應(yīng)用中適用,而不適用于那些生成和修改數(shù)據(jù)庫的應(yīng)用。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)。一般來說,當(dāng)信息系統(tǒng)的問題被確定時(shí),僅僅粗略地嘗試概念數(shù)據(jù)建模。這通常是一個(gè)新的數(shù)據(jù)庫,它復(fù)制現(xiàn)存系統(tǒng)的一部分,還可能增加了一些新的內(nèi)容。 當(dāng)產(chǎn)生原型新的版本時(shí)重復(fù)數(shù)據(jù)庫的實(shí)現(xiàn)和維護(hù)活動(dòng)。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)。如果系統(tǒng)(包括數(shù)據(jù)庫)效率很低,那么系統(tǒng)和數(shù)據(jù)庫將被重新編程和重新組織以達(dá)到期望的性能。使用原型法改變用戶報(bào)表和顯示的內(nèi)容和布局是相當(dāng)容易的。甚至有可能為一個(gè)需要新的數(shù)據(jù)庫的系統(tǒng)使用原型法,在這種情況下,當(dāng)系統(tǒng)需求在迭代的開發(fā)過程中不斷變化時(shí)需要獲取樣本數(shù)據(jù)以建造或重建數(shù)據(jù)庫原型。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
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