計算機相關技術外文資料翻譯模板

1、畢業(yè)設計(論文)外文資料翻譯系 別 計算機信息與技術系 專 業(yè) 計算機科學與技術 班 級 B070601 姓 名 魏博 學 號 B07060136 外文出處 附 件 1. 原文； 2. 譯文 2011年3月database development processBased on information engineering information systems planning database is a source of development projects. These new database development projects is usually in order t

2、o meet the strategic needs of organizations, such as improving customer support, improve product and inventory management, or a more accurate sales forecast. However, many more database development project is the bottom-up approach emerging, such as information system user needs specific information

3、 to complete their work, thus beginning a project request, and as other information systems experts found that organizations need to improve data management and begin new projects. Bottom-up even in the circumstances, to set up an enterprise data model is also necessary to understand the existing da

4、tabase can provide the necessary data, otherwise, the new database, data entities and attributes can be added to the current data resources to the organization.Both the strategic needs or operational information needs of each database development projects normally concentrated in a database. Some pr

5、ojects only concentrated in the database definition, design and implementation of a database, as a follow-up to the basis of the development of information systems. However, in most cases, the database and associated information processing function as a complete information systems development proje

6、ct was part of the development. 2.1 System Development Life Cycle Guide management information system development projects is the traditional process of system development life cycle (SDLC). System development life cycle is an organization of the database designers and programmers information system

7、 composed of the Panel of Experts detailed description, development, maintenance and replacement of the entire information system steps. This process is because Waterfall than for every step into the adjacent the next step, that is, the information system is a specification developed by a piece of l

8、and, every piece of the output is under an input. However shown in the figure, these steps are not purely linear, each of the steps overlap in time (and thus can manage parallel steps), but when the need to reconsider previous decisions, but also to roll back some steps ahead. (And therefore water c

9、an be put back in the waterfall!) The system development life cycle including each stage and database development-related activities, therefore, the question of database management systems throughout the entire development process. In Figure 5 we repeat of the system development life cycle stage of

10、the seven, and outlines the common database at each stage of development activities. Please note that the systems development life cycle stages and database development steps exists between the relationship between the concept of modeling data in both systems development life cycle stages between.1.

11、Enterprise 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 activiti

12、es, 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

13、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.2.Conceptual Data Modeling One has already begun on the Information System project, the concept of data mode

14、ling 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

15、in the scope of the required data. This category only includes high-level data (entities), and main contact. Then in the system development life-cycle analysis stage must have a management information system set the entire organization Details of the data model definition of all data attributes, lis

16、ting all data types that all data inter-entity 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 o

17、f 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 follow-up information system life cycle activities in the design of services, statements, display and inqui

18、ries may find that missing element or mistakes. Therefore, the concept of data often said that modeling is a top-down 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 Logi

19、cal 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 computer procedures (including procedures for the input and output

20、format), database support services, statements, and inquiries revealed that a detailed examination. In this so-called Bottom-up 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 ea

21、ch separate statements, services, and so on the analysis must take into account a specific, limited but complete database view. When statements, services, and other analysis might be necessary to change the concept of data model. Especially in large-scale projects, the different analytical systems d

22、evelopment 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 independen

23、t or merged into a comprehensive 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 t

24、he formation of good data specifications and determine the rules, the combination, the data after consultation specifications or converted into basic atomic element. Most of today's database, these rules from the relational database theory and the process known as standardization, #. This step i

25、s the result of management of these data have not cited any database management system for a complete description of the database map. Logical database design completed, we began to identify in detail the logic of the computer program and maintenance, the report contents of the database for inquirie

26、s. 4. Physical database design and definitionPhysical database design and definition phase decisions computer 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

27、desired management information and decision support statements. The objective of this stage is to design an effective and safe management of all data-processing database, the physical database design to closely integrate the information systems of other physical aspects of the design, including proc

28、edures, computer hardware, operating systems and data communications networks. 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)

29、, the dedicated database processing languages (such as SQL), or the process of the non-exclusive 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 completion of all the database files,

30、 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 inte

31、rmediate 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

32、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

33、 structure of the database. When a procedure or failure of the computer 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 d

34、evelopment 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. 2.2 Information System developed by other means System Development Life Cycle minor changes in law

35、or its variant of the often used to guide information systems and database development. Information System is a life-cycle 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

36、system and it must communications 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 an

37、d more organizations 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 enha

38、nce system is mainly to the application of data retrieval application, but not to those who generate and modify database applications. The most widely used method of rapid application development is one of the prototype. The prototype system is a method of iterative development process, analysts and

39、 users through close co-operation, continuing to revise the system will eventually convert all the needs of a working system. In this diagram we contains notes, briefly describes each stage of the prototype of the database development activities. Normally, when information systems problems were iden

40、tified, tried only a rough concept of data modeling. In the development of the initial prototype, the design of the user wants to display and statements, and that any new database needs and define a term prototype database. This is usually a new database, copy the part of the existing system, but mi

41、ght also added some new content. When the need for new content, these elements are usually from external data sources, such as market research data, the general economic indicators or industry standards. When a prototype of a new version to repeat the achievement and maintenance of database activiti

42、es. Usually only a minimum level of security and integrity control, because at this time the focus is as soon as possible to produce a prototype version can be used. But document management project also deferred to the final, only be used in the delivery of user training. Finally, once constructed a

43、n acceptable prototype, developers, and users will be the final decision of whether to prototype delivery and the use of the database. If the system (including database) efficiency is very low, then the system and database will be re-programming and re-organization in order to achieve the desired pe

44、rformance. Along with visual programming tools (such as Visual Basic, Java, Visual C + + and fourth generation language) increasingly popular use of visual programming tools can easily change the user interface with the system, the prototype is becoming the choice of system development methodology.

45、Customers using the prototype method statements and show changes to the content and layout is quite easy. In the process, the new database needs were identified, so it is the development of the use of the existing database should be amended. There is even the possibility of a need for a new database

46、 system prototype method, in such circumstances, when the system demand in the iterative process of development in the ever-changing needs access to sample data, the construction or reconstruction of the database prototype. 數(shù)據庫開發(fā)過程基于信息工程的信息系統(tǒng)規(guī)劃是數(shù)據庫開發(fā)項目的一個來源。這些開發(fā)新數(shù)據庫的項目通常是為了滿足組織的戰(zhàn)略需求，例如改善客戶支持、提高產品和庫存

47、管理或進行更精確的銷售預測。然而許多數(shù)據庫開發(fā)項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，從而請求開始一個項目，又如其他信息系統(tǒng)的專家發(fā)現(xiàn)組織需要改進數(shù)據管理而開始新的項目。即使在自底向上的情況下，建立企業(yè)數(shù)據模型也是必須的，以便理解現(xiàn)有的數(shù)據庫是否可以提供所需的數(shù)據，否則，新的數(shù)據庫、數(shù)據實體和屬性都應該加到當前的組織數(shù)據資源中去。無論是戰(zhàn)略需求還是操作信息的需求，每個數(shù)據庫開發(fā)項目通常集中在一個數(shù)據庫上。一些數(shù)據庫項目僅僅集中在定義、設計和實現(xiàn)一個數(shù)據庫，以作為后續(xù)信息系統(tǒng)開發(fā)的基礎。然而在大多數(shù)情況下，數(shù)據庫及其相關信息處理功能是作為一個完整的信

48、息系統(tǒng)開發(fā)項目的一部分而被開發(fā)的。2.1 系統(tǒng)開發(fā)生命周期指導管理信息系統(tǒng)開發(fā)項目的傳統(tǒng)過程是系統(tǒng)開發(fā)生命周期(SDLC)。系統(tǒng)開發(fā)生命周期是指一個組織中由數(shù)據庫設計人員和程序員組成的信息系統(tǒng)專家小組詳細說明、開發(fā)、維護和替換信息系統(tǒng)的全部步驟。這個過程比作瀑布是因為每一步都流到相鄰的下一步，即信息系統(tǒng)的規(guī)格說明是一塊一塊地開發(fā)出來的，每一塊的輸出是下一塊的輸入。然而如圖所示，這些步驟并不是純線性的，每個步驟在時間上有所重疊（因此可以并行地管理步驟），而且當需要重新考慮先前的決策時，還可以回滾到前面某些步驟。（因而水可以在瀑布中倒流！）系統(tǒng)開發(fā)生命周期的每一階段都包括與數(shù)據庫開發(fā)相關的活動，所

49、以，數(shù)據庫管理的問題遍布整個系統(tǒng)開發(fā)過程。請注意，系統(tǒng)開發(fā)生命周期的階段和數(shù)據庫開發(fā)步驟之間不存在一一對應的關系，概念數(shù)據建模發(fā)生在兩個系統(tǒng)開發(fā)生命周期階段之間。· 企業(yè)建模 數(shù)據庫開發(fā)過程從企業(yè)建模（系統(tǒng)開發(fā)生命周期中項目論證和選擇階段的一部分）開始，設定組織數(shù)據庫的范圍和一般內容。企業(yè)建模發(fā)生在信息系統(tǒng)規(guī)劃和其他活動期間，這些活動確定信息系統(tǒng)的哪個部分需要改變和加強并概述出全部組織數(shù)據的范圍。在這一步中，檢查當前數(shù)據庫和信息系統(tǒng)，分析作為開發(fā)項目主體的業(yè)務領域的本質，用非常一般的術語描述每個信息系統(tǒng)在開發(fā)時所需要的數(shù)據。每個項目只有當它達到組織的預期目標時才可以進行下一步。

50、83; 概念數(shù)據建模 對一個已經開始的信息系統(tǒng)項目而言，概念數(shù)據建模階段分析信息系統(tǒng)的全部數(shù)據需求。它分為兩個階段。首先，它在項目開始和規(guī)劃階段建立一張圖。同時建立其他文檔來概述不考慮現(xiàn)存數(shù)據庫的情況下特定開發(fā)項目中所需的數(shù)據范圍。此時僅僅包括高層類別的數(shù)據（實體）和主要聯(lián)系。然后在系統(tǒng)開發(fā)生命周期的分析階段產生確定信息系統(tǒng)必須管理的全部組織數(shù)據的詳細數(shù)據模型，定義所有數(shù)據屬性，列出全部數(shù)據類別，表示數(shù)據實體間所有的業(yè)務聯(lián)系，確定描述數(shù)據完整性的全部規(guī)則。在分析階段，還要檢查概念數(shù)據模型（在后面也稱作概念模式）與用來解釋目標信息系統(tǒng)其他方面的模型類別的一致性，例如處理步驟、處理數(shù)據的規(guī)則以及時

51、間的時序。然而，即使是這樣詳細的概念數(shù)據模型也只是初步的，因為后續(xù)的信息系統(tǒng)生命周期中的活動在設計事務、報表、顯示和查詢時可能會發(fā)現(xiàn)遺漏的元素或錯誤。因此，經常說到的概念數(shù)據建模是以一種自頂向下的方式完成的，它由業(yè)務領域的一般理解所驅動，而不是由特定的信息處理活動所驅動。3.邏輯數(shù)據庫設計邏輯數(shù)據庫設計從兩個角度進行數(shù)據庫開發(fā)。首先，將概念數(shù)據模型變換成基于關系數(shù)據庫理論的標準表示方法關系。然后像設計信息系統(tǒng)的每個計算機程序（包括程序的輸入和輸出格式）那樣，對數(shù)據庫支持的事務、報表、顯示和查詢進行詳細的檢查。在這個所謂的自底向上的分析中，精確地驗證數(shù)據庫中需要維護的數(shù)據和在每個事務、報表等等中

52、需要的那些數(shù)據的性質。對于每個單獨的報表、事務等等的分析都要考慮一個特定的、有限制的但是完全的數(shù)據庫視圖。當報表、事務等被分析時有可能根據需要而改變概念數(shù)據模型。尤其在大型的項目中，不同的分析人員和系統(tǒng)開發(fā)者的團隊可以獨立地工作在不同的程序或程序集中，他們所有工作的細節(jié)直到邏輯設計階段才可能會顯示出來。在這種情況下，邏輯數(shù)據庫設計階段必須將原始的概念數(shù)據模型和這些獨立的用戶視圖合并或集成到一個全面的設計中。在進行邏輯信息系統(tǒng)設計時也可以確定額外的信息處理需求，此時這些新的需求必須集成到前面確定的邏輯數(shù)據庫設計中。邏輯數(shù)據庫設計的最后一步是根據為生成結構良好的數(shù)據規(guī)格說明而確定的規(guī)則，將組合的、協(xié)商后的數(shù)據規(guī)格說明轉換成基本的或原子的元素。對當今的大部分數(shù)據庫而言，這些規(guī)則來自關系數(shù)據庫理論和稱作規(guī)范化的過程。這一步的結果是產生管理這些數(shù)據的、不引用任何數(shù)據庫管理系統(tǒng)的完整的數(shù)據庫描述圖。在完成邏輯數(shù)據庫設計后，開始確定詳細的計算機程序的邏輯和維護、報告數(shù)據