版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請進行舉報或認領(lǐng)
文檔簡介
1、畢業(yè)設(shè)計(論文)外文資料翻譯系 別 計算機信息與技術(shù)系 專 業(yè) 計算機科學與技術(shù) 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(jù)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(jù)庫開發(fā)項目的一個來源。這些開發(fā)新數(shù)據(jù)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(chǎn)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(jù)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(jù)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(jù)模型也是必須的,以便理解現(xiàn)有的數(shù)據(jù)庫是否可以提供所需的數(shù)據(jù),否則,新的數(shù)據(jù)庫、數(shù)據(jù)實體和屬性都應該加到當前的組織數(shù)據(jù)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(jù)庫開發(fā)項目通常集中在一個數(shù)據(jù)庫上。一些數(shù)據(jù)庫項目僅僅集中在定義、設(shè)計和實現(xiàn)一個數(shù)據(jù)庫,以作為后續(xù)信息系統(tǒng)開發(fā)的基礎(chǔ)。然而在大多數(shù)情況下,數(shù)據(jù)庫及其相關(guān)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(jù)庫設(shè)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?。┫到y(tǒng)開發(fā)生命周期的每一階段都包括與數(shù)據(jù)庫開發(fā)相關(guān)的活動,所
49、以,數(shù)據(jù)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(jù)庫開發(fā)步驟之間不存在一一對應的關(guān)系,概念數(shù)據(jù)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(jù)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(shè)定組織數(shù)據(jù)庫的范圍和一般內(nèi)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(jù)的范圍。在這一步中,檢查當前數(shù)據(jù)庫和信息系統(tǒng),分析作為開發(fā)項目主體的業(yè)務領(lǐng)域的本質(zhì),用非常一般的術(shù)語描述每個信息系統(tǒng)在開發(fā)時所需要的數(shù)據(jù)。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(jù)建模 對一個已經(jīng)開始的信息系統(tǒng)項目而言,概念數(shù)據(jù)建模階段分析信息系統(tǒng)的全部數(shù)據(jù)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(jù)庫的情況下特定開發(fā)項目中所需的數(shù)據(jù)范圍。此時僅僅包括高層類別的數(shù)據(jù)(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(chǎn)生確定信息系統(tǒng)必須管理的全部組織數(shù)據(jù)的詳細數(shù)據(jù)模型,定義所有數(shù)據(jù)屬性,列出全部數(shù)據(jù)類別,表示數(shù)據(jù)實體間所有的業(yè)務聯(lián)系,確定描述數(shù)據(jù)完整性的全部規(guī)則。在分析階段,還要檢查概念數(shù)據(jù)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(jù)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(jù)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(shè)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(jīng)常說到的概念數(shù)據(jù)建模是以一種自頂向下的方式完成的,它由業(yè)務領(lǐng)域的一般理解所驅(qū)動,而不是由特定的信息處理活動所驅(qū)動。3.邏輯數(shù)據(jù)庫設(shè)計邏輯數(shù)據(jù)庫設(shè)計從兩個角度進行數(shù)據(jù)庫開發(fā)。首先,將概念數(shù)據(jù)模型變換成基于關(guān)系數(shù)據(jù)庫理論的標準表示方法關(guān)系。然后像設(shè)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(jù)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(jù)庫中需要維護的數(shù)據(jù)和在每個事務、報表等等中
52、需要的那些數(shù)據(jù)的性質(zhì)。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(jù)庫視圖。當報表、事務等被分析時有可能根據(jù)需要而改變概念數(shù)據(jù)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(shè)計階段才可能會顯示出來。在這種情況下,邏輯數(shù)據(jù)庫設(shè)計階段必須將原始的概念數(shù)據(jù)模型和這些獨立的用戶視圖合并或集成到一個全面的設(shè)計中。在進行邏輯信息系統(tǒng)設(shè)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(jù)庫設(shè)計中。邏輯數(shù)據(jù)庫設(shè)計的最后一步是根據(jù)為生成結(jié)構(gòu)良好的數(shù)據(jù)規(guī)格說明而確定的規(guī)則,將組合的、協(xié)商后的數(shù)據(jù)規(guī)格說明轉(zhuǎn)換成基本的或原子的元素。對當今的大部分數(shù)據(jù)庫而言,這些規(guī)則來自關(guān)系數(shù)據(jù)庫理論和稱作規(guī)范化的過程。這一步的結(jié)果是產(chǎn)生管理這些數(shù)據(jù)的、不引用任何數(shù)據(jù)庫管理系統(tǒng)的完整的數(shù)據(jù)庫描述圖。在完成邏輯數(shù)據(jù)庫設(shè)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(jù)
溫馨提示
- 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
- 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會有圖紙預覽,若沒有圖紙預覽就沒有圖紙。
- 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
- 5. 人人文庫網(wǎng)僅提供信息存儲空間,僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護處理,對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對任何下載內(nèi)容負責。
- 6. 下載文件中如有侵權(quán)或不適當內(nèi)容,請與我們聯(lián)系,我們立即糾正。
- 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。
最新文檔
- 學生資助先進單位事跡15篇
- 幽默婚宴父親致辭(集合15篇)
- 感人的勵志演講稿
- 學生會活動策劃部迎新
- 開學安全教育學習
- 開學講話稿15篇
- 考慮邊界層相互作用的雙層葉片垂直軸風力機氣動特性研究
- 基于大型砂箱模擬試驗的層狀包氣帶水分時空運移特征研究
- 智研咨詢發(fā)布-2024年中國分布式能源管理系統(tǒng)行業(yè)現(xiàn)狀、發(fā)展環(huán)境及投資前景分析報告
- 動漫知識大比拼
- 2025-2030年中國清真食品行業(yè)運行狀況及投資發(fā)展前景預測報告
- 廣東省茂名市電白區(qū)2024-2025學年七年級上學期期末質(zhì)量監(jiān)測生物學試卷(含答案)
- 《教育強國建設(shè)規(guī)劃綱要(2024-2035年)》全文
- 2025年河南洛陽市孟津區(qū)引進研究生學歷人才50人歷年高頻重點提升(共500題)附帶答案詳解
- 2025年度軍人軍事秘密保護保密協(xié)議與信息安全風險評估合同3篇
- 數(shù)字化轉(zhuǎn)型中的職業(yè)能力重構(gòu)
- 2025屆高中數(shù)學一輪復習專練:橢圓(含解析)
- 中國服裝零售行業(yè)發(fā)展環(huán)境、市場運行格局及前景研究報告-智研咨詢(2025版)
- 汽車車身密封條設(shè)計指南
- 2024建安杯信息通信建設(shè)行業(yè)安全競賽題庫(試題含答案)
- 術(shù)后譫妄及護理
評論
0/150
提交評論