信息与计算科学毕业设计
Advanced Database Applications
The 1990s have seen significant changes in the computer industry. In database systems, we have seen the widespread acceptance of RDBMSs for traditional business applications, such as order processing, inventory control, banking, and airline reservations. However, existing RDBMSs have proven inadequate for applications whose needs are quite different from those of traditional business database applications. These applications include:
■computer-aided design (CAD);
■computer-aided manufacturing (CAM);
■computer-aided software engineering (CASE);
■office information systems (OIS) and multimedia systems;
■digital publishing;
■eographic information systems (GIS);
■interactive and dynamic Web sites.
Computer-aided design (CAD)
A CAD database stores data relating to mechanical and electrical design covering, for example, buildings, aircraft, and integrated circuit chips. Designs of this type have some common characteristics:
■Design data is characterized by a large number of types, each with a small number of instances.
Conventional databases are typically the opposite. For example, the DreamHome database consists of only a dozen or so relations, although relations such as PropertyForRent, Client, and Viewing may contain thousands of tuples.
■Designs may be very large, perhaps consisting of millions of parts, often with many interdependent subsystem designs.
■The design is not static but evolves through time. When a design change occurs, its implications must be propagated through all design representations. The dynamic nature of design may mean that some actions cannot be foreseen at the beginning.
■Updates are fat-reaching because of topological or functional relationships, tolerances, and so on. One change is likely to affect a large number of design objects.
■Often, many design alternatives are being considered for each component, and the correct version for each part must be maintained. This involves some form of version control and
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configuration management.
■There may be hundreds of staff involved with the design, and they may work in parallel on multiple versions of a large design. Even so, the end-product must be consistent and coordinated. This is sometimes referred to as cooperative engineering.
Computer-aided manufacturing （CAM）
A CAM database stores similar data to a CAD system, in addition to addition to data relating to discrete production (such as cars on an assembly line) and continuous production (such as chemical synthesis). For example, in chemical manufacturing there will be applications that monitor information about the state of the system, such as reactor Bessel temperatures, flow rates, and yields. There will also be applications that control various physical processes, such as opening valves, applying more heat to reactor vessels, and increasing the flow of cooling systems. These applications are often organized in a hierarchy, with a top-level application monitoring the entire factory and lower=level applications monitoring individual manufacturing processes. These applications must respond in real time and be capable of adjusting processes to maintain optimum performance within tight tolerances. The applications use a combination of standard algorithms and custom rules to respond to different conditions. Operators may modify these rules occasionally to optimize performance based on complex historical data that the system has to maintain. In this example, the system has to maintain large volumes of data that is hierarchical in nature and maintain complex relationships between the data. It must also be able to rapidly navigate the data to review and respond to changes.
Computer-aided software engineering (CASE)
A CASE database stores data relating to stages of the software development lifecycle: planning, requirements collection and analysis, design, implementation, testing, maintenance, and documentation. As with CAD, designs may be extremely large, and cooperative engineering is the norm. For example, software configuration management tools allow concurrent sharing of project design, code, and documentation. They also track the dependencies between these components and assist with change management. Project management tools facilitate the coordination of various project management activities, such as the scheduling of potentially highly complex interdependent tasks, cost estimation, and progress monitoring.
Network management systems
Network management systems coordinate the delivery of communication services across a
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信息与计算科学毕业设计
computer network. These systems perform such tasks as network path management, problem management, and network planning. As with the chemical manufacturing example we discussed earlier, these systems also handle complex data and require real-time performance and continuous operation. For examples, a telephone call might involve a chain of network switching devices that route a message from sender to receiver, such as:
Node?Link?Node?Link?Node?Link?Node
Where each Node represents a port on a network device and each Link represents a slice of bandwidth reserved for that connection. However, a node may participate in several different connections and any database that is created has to manage a complex graph of relationships. To route connections, diagnose problems, and balance loadings, the network management systems have to be capable of moving through this complex graph in real time.
Office information systems (OIS) and multimedia systems
An OIS database stores data relating to the computer control of information in a business, including electronic mail, documents, invoices, and so on. To provide better support for this area, we need to handle a wider range of data types other than names, addresses, dates, and money. Modern systems now handle free-form text, photographs, diagrams, and audio and video sequences. For example, a multimedia document may handle text, photographs, spreadsheets, and voice commentary. The documents may have a specific structure imposed on them, perhaps described using a mark-up language such as SGML (Standardized Generalized Markup Language), HTML (HyperText Markup Language), or XML (eXtended Markup Language), as we discuss in Chapter 29.
Documents may be shared among many users using systems such as electronic mail and bulletin-boards based on Internet technology. Again ,such applications need to store data that has a much richer structure than tuples consisting of numbers and text strings. There is also an increasing need to capture handwritten notes using electronic devices. Although many notes can be transcribed into AS CⅡtext using handwriting analysis techniques, most such data cannot. In addition to words, handwritten data can include sketches, diagrams and so on.
In the DreamHome case study, we may find the following requirements for handling multimedia.
■Image data A client may query an image data base of properties for rent. Some queries may simply use a textual description to identify images of desirable properties. In other cases it may
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be useful for the client to query using graphical images of features that may be found in desirable properties (such as bay windows, internal cornicing, or roof gardens).
■Video data A client may query a video database of properties for rent. Some queries may simply use a textual description to identify the video images of desirable properties. In other cases it may be useful for the client to query using video features of the desired properties (such as views of the sea or surrounding hills).
■Audio data A client may query an audio database that describes the features of properties for rent. Some queries may simply use a textual description to identify the desired property. In other cases it may be useful for the client to use audio features of the desired properties (such as the noise level from nearby traffic).
■Handwritten data A member of staff may create notes while carrying out inspections of properties for rent. At a later data, he or she may wish to query such data to find all notes made about a flat in Novar Drive with dry rot.
Digital publishing
The publishing industry is likely to undergo profound changes in business practices over the next decade. It is becoming possible to store books, journals, papers, and articles electronically and deliver them over high-speed networks to consumers. As with office information systems, digital publishing is being extended to handle multimedia documents consisting of text, audio, image, and video data and animation. In some cases, the amount of information available to be put online is enormous, in the order of petabytes (1015 bytes), which would make them the largest databases that a DBMA has ever had to manage.
Geographic information systems (GIS)
A GIS database stores various types of spatial and temporal information, such as that used in land management and underwater exploration. Much of the data in these systems is derived from survey and satellite photographs, and tends to be very large. Searches may involve identifying features based, for example, on shape, color, or texture, using advanced pattern-recognition techniques.
For example, EOS (Earth Observing System) is a collection of satellites launched by NASA in the 1990s to gather information that will support sci8entists concerned with long-term trends regarding the earth’s atmosphere, oceans, and land. It is anticipated that these satellites will return over one-third of a petabyte of information per year. This data will be integrated with other data
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信息与计算科学毕业设计
sources and will be stored in EOSDIS (EOS Data and Information System). EOSDIS will supply the information needs of both scientists and non-scientists. For example, schoolchildren will be able to access EOSDIS to see a simulation of world weather patterns. The immense size of this database and the need to support thousands of users with very heavy volumes of information requests will provide many challenges for DBMSs.
Interactive and dynamic Web sites
■Consider a Web site that has an online catalog for selling clothes. The Web site maintains a set of preferences for previous visitors to the site and allows a visitor to:
■browse through thumbnail images of the items in the catalog and select one to obtain a full-size image with supporting details;
■search for items that match a user-defined set of criteria;
■obtain a 3D rendering of any item of clothing based on a customized specification (for example, color, size, fabric);
■modify the rendering to account for movement, illumination, backdrop, occasion, and so on;
■select accessories to go with the outfit, from items presented in a sidebar;
■select a voiceover commentary giving additional details of the item;
■view a running total of the bill, with appropriate discounts;
■conclude the purchase through a secure online transaction.
The requirements for this type of application are not that different from some of the above advanced applications: there is a need to handle multimedia content (text, audio, image, video data, and animation) and to interactively modify the display based on user preferences and user selections. As well as handling complex data, the site also has the added complexity o9f providing 3D rendering. It is argued that in such a situation the database is not just presenting information to the visitor but is actively engaged in selling, dynamically providing customized information and atmosphere to the visitor (King, 1997).
As we discuss in Chapters 28 and 29, the Web now provides a relatively new paradigm for data management, and languages such as XML hold significant promise, particularly for the e-Commerce market. The Forrester Research Group is predicting that business-to-business transactions will rise by 99% annually and is expected to reach US$1.3 trillion by 2003. in addition, e-Commerce is expected to account for US$3.2 trillion in worldwide corporate revenue by 2003 and potentially represent 5% of sales in the global economy. As the use of the Internet
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increases and the technology becomes more sophisticated, then we will see Web sites and business-to-business transactions handle much more complex and interrelated data.
Other advanced database applications include:
■Scientific and medical applications, which may store complex data representing systems such as molecular models for synthetic chemical compounds and genetic material.
■Expert systems, which may store knowledge and rule bases for artificial intelligence (AI) applications.
■Other applications with complex and interrelated objects and procedural data.
原文摘自2004年出版的Database Systems A Practical Approach to Design Implementation and Management第580页
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信息与计算科学毕业设计
高级数据库应用
20世纪90年代，计算机工业发生了巨大变化。在数据库方面，可以看到RDBMS广泛应用于传统行业，例如订单处理、库存控制、银行业务、航班预定等。然而，现在的RDBMS对于一些与传统数据库应用差别较大的新应用则表现出明显的不足。这些应用包括：
■计算机辅助设计（CAD）
■计算机辅助制造（CAM）
■计算机辅助软件工程（CASE）
■网络管理系统
■办公信息系统（OIS）和多媒体系统
■数字出版
■地理信息系统
■交互和互动的Web站点。
计算机辅助设计（CAD）
CAD数据库中存储着与机械或电子设计相关的数据，例如建筑物、飞行器以及集成电路芯片。这种类型的设计具有一些普遍的特征：
■设计数据具有多类型的特点，每一种类型都有较小数量的实例。而传统的数据库与之正好相反。例如，DreamHome数据库只有大约12个关系，而一些关系，如PropertyForRent,Client和Viewing可能含有数千个组。
■设计规模大，有可能包含几百万个组成部分，同时还有许多相互依赖的子系统设计。
■设计不是静止的，而是随着时间的推移在变化。.当一个设计发生改变时，相关信息必须能被传递给所有的设计表示。设计的动态特征性意味着在设计开始时，一些动作可能是无法预见的。
■由于拓扑结构或功能的关联、容错等因素的影响，更新十分复杂。单个修改可能会影响到许多涉及对象。
■通常情况下，每个组件考虑多种设计选择，因此每一个组件都需要维护正确的版本。这就涉及到某种形式的版本控制和配置管理。
■可能有数以百计的设计人员参与设计，并且他们并行的在一个大型设计的多
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个版本上工作。其实这样，最终产品必须是椅子和协调的。这有时称为协作工程。
计算机辅助制造（CAM）
CAM数据库中除了存储与CAD系统类似的数据外，还包含与离散产品（如装配线上的汽车）和连续产品（如化学化合物）相关的数据。例如在化学制剂生产中，可能会有监视系统状态信息（例如反应堆容器的温度、流量和产量）的应用程序。还可能有控制各种各样物理过程的应用，比如打开阀门、给反应堆容器加热和增加冷却系统的流量。这些应用通常是以层次的方式组织起来的，高层的应用监视整个工厂，低层的应用监视单个生产过程。这些应用必须实时地做出反应，并且能够调节过程以保证在固定的承受能力范围内保持较优的性能。这些应用使用标准算法以定制规范相结合一对不同的情况做出反应。操作人员可以随时基于系统必须保持的复杂历史数据优化性能，调整这些规则。在这个例子中，系统必须保持大量的分层次的数据，还必须保持这些数据之间的复杂关系。他还必须能够快速定位需要查看得数据对变化做出反应。
计算机辅助软件工程（CASE）
CASE数据库存储着与软件开发周期的各个阶段相关的数据：规划、需求收集和分析、设计、实现、测试、维护和文档。与CAD类似，设计可能非常大，并且一般的协作工程。例如，软件配置管理工具允许项目设计、代码和文档的并发共享。此外，他还要追踪这些组成部分之间的相互依赖的任务的进度安排、成本估算和进展监控。
网络管理系统
网络管理系统协调计算机网络中通信服务的传递。这些系统执行诸如网络路径管理、问题管理和网络规划等任务。和前面曾经讨论过的化学制剂生产的例子相似，这些系统还要处理复杂的数据，并且要求实时执行和连续操作。例如：一次电话呼叫可能涉及一系列的网络交换设备来将一个信息从发送者传收到接收者；
Node?Link?Node?Link?Node?Link?Node
其中每一个节点（Node）代表网络设备上的一个端口，每一个链路（Link）代表保留给那个连接的一段带宽。然而，一个节点可能有多个不同的连接，创建的任何数据库都必须要处理一个复杂的关系图。威力路由连接、诊断问题和负载平衡，网络管理系统必须具有实时在这个复杂的图中移动的能力。
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信息与计算科学毕业设计
办公信息系统（OIS）和多媒体系统
OIS数据库存储着与计算机控制的商务信息相关的数据，包括电子邮件、文档、发票等。威力对这个领域提供较好的支持，除了名称、地址、时间和资金以外，还需要处理广泛的数据类型。目前，现代系统可以处理自由形式的文本、照片、表格、音频和视频序列。例如，一个多媒体文档可能包含文本、照片、电子数据表和语音解说。文档可能需要具有要求的特定结构，这可能是石油标记语言，如SGML（标准化通用标记语言）、HTML（超文本标记语言）或者XML （可扩展标记语言）等来描述，将在29章中讨论。
文档可能利用诸如基于Internet技术的电子邮件和公告板系统在许多用户中共享。这样的应用也需要存储比数字和文本串型元组结构更丰富的数据。使用电子设备手写输入的需求也在日益上升。尽管许多记录可以使用手写分析技术描述成AS CⅡ文本，但大多数这样的数据还是很难描述的。除了文字以外，手写数据还可能包含草图、表格等。
在DreamHouse案例中，可以发现对于多媒体处理的下列要求：
■图像数据：客户可能查询一个出租房产的图像数据库。一些查询可能只是简单地使用文本的描述来标识想要房产的图像。但在某些情形下，若能使用所希望的房产的某些图像特征（例如凸窗、内檐口或屋顶花园）进行查询更好。■视频数据：客户可能查询一个视频出租房产数据库。一些查询可能只是简单的使用文本的描述来识别想要查询的房产的视频图像。但也存在某些情形，用户使用所希望房产的某些视频特征（例如海景或群山环绕）来查询会更好。■音频数据：客户可能查询一个音频出租房产数据库。一些查询可能只是简单的使用文本的描述来识别想要的房产。但也会存在某些情形，若能使用所希望的房产的某些音频特征（例如附近交通噪声）查询可能会更好。
■手写数据：工作人员可能在检查出租房产的同时进行记录。一段时间后，他可能会希望查询这些数据，以获得曾记录过的位于Nover Drive的一些公寓信息。
数字出版
在未来10年里，出版业早商务实践上可能会经历深远的变化。以电子形式存储书籍、杂志、论文和文章，并且通过高速网络将它们传送给消费者已经成为可能。在办公信息系统的支持下数字出版能够处理包含文本、音频、图像视频数据和动画组成的多媒体文档。在某些情况下，防盗网山的数据量大，可能已PB
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为单位，这是DBMS有史以来管理过的最大型的数据库。
地理信息系统（GIS）
GIS数据库存储着各种类型的空间和时间信息，例如用于土地管理和水下资源开发的数据。
系统数据中的大部分时通过勘测和卫星图片获得的，数据量很大。可以使用先进的模式识别技术根据外形、颜色材质等标识特征搜索。
例如，EOS(Earth Observing System,地球观测系统)是一组由NASA在20世纪90年代发射的卫星，目的是为了收集信息，能够支持科学家对地球的大气、海洋和陆地的长期发展趋势的研究。据估计，这些卫星每年会返回1/3 PB以上的数据的信息。这些数据将与其他数据源综合，存储到EOSDIS(EOS Data and Information System,EOS数据和信息系统)中。EOSDIS将同时为科学家和其他人员提供所需要的信息。例如，学生将可以访问EOSDIS看到世界气候模式的模拟。数据库的巨大规模，以及支持数以千计的用户所提出的大量信息查询的能力，都给DMBMS带来了许多挑战。
交互和动态的Web站点
考虑一个有在线目录的销售服装的Web站点。站点保持着本站点的访问者偏爱信息的同居数据，并且允许访问者：
■浏览目录中所有项目的缩略图像，并且可以选定其中一个得到完全大小的图像以详细信息
■寻找符合用户定义一组标准的项目。
■得到一个基于定制规格（例如，颜色、尺码、质地）的任意服装款式的3D透视图。
■根据移动、照明、背景、场合等调整地透视图。
■在工具条中列出的项目中的选择附件进行搭配。
■选择一个画外音解说，给出关于这种款式的更加详细的信息。
■查看到合适的折扣的流水帐单。
■通过安全的在线交易技术完成购买。
这种类型的应用的要求与上面所述的一些高级应用并没有什么不同：需要处理多媒体内容（文本、音频、图像、视频数据以及动画），并且能够根据用户的喜爱和用户的选择交互式的修改显示。除了处理复杂的数据外，站点还因为要提供3D透视图而增加了复杂度。一些人争论说，在这种情况下数据库不仅仅为访
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信息与计算科学毕业设计
问者提供信息，还要及参与出售、动态提供定制信息并创造对访问者友好的气氛（King,1997）.
在第28章和29章将介绍， Web现在为数据管理提供了一个新范例及XML 等很有前途的语言（尤其对电子商务市场）。Forrester研究组预言，B2B模式的商务活动将以每年99%的速度增长，并预期在2003年将达到1.3万亿美元。此外在2003年，电子商务将可达到3.2万亿的全球总收入占全球经济销售额的5%。随着Interent的普及以及技术的更加复杂，Web站点和企业对企业交易将处理更加复杂和相关连的数据。
其他一些高级的数据库应用包括：
■科学和医学应用，存储复杂的数据，用来描述一些复杂系统，例如早合成化学化合物和基因素材的分子模型的系统。
■专家系统，存储人工智能（AI）应用的知识和规则。
■其他有复杂和相关联对象和过程数据的应用。
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Database Management System Source：Database and Network Journal Author：David Anderson You know that a data is a collection of logically related data elements that may be structured in various ways to meet the multiple processing and retrieval needs of orga nizations and individuals. There’s nothing new about data base-early ones were chiseled in stone, penned on scrolls, and written on index cards. But now database are commonly recorded on magnetically media, and computer programs are required to perform the necessary storage and retrieval operations. The system software package that handles the difficult tasks associated with created, accessing, and maintaining database records is in a DBMS package establish an interface between the database itself and the users of the database. (These users may be applications programmers, managers and others with information needs, and various OS programmers.) A DBMS can organize, process, and present selected data elements from the database. This capability enables decision makers to search. Probe, and query data contents in order to extract answers to nonrecurring and unplanned questions that aren’t available in regular reports. These questions might initially be vague and/or poorly defined, but people can “browse” through the database until they have the needed information. In short, the DBMS will “manage” the stored data items and assemble the needed items from the common database in response to the queries of those who aren’t programmers. In a file-oriented system, users needing special information may communicate their needs to a programmers, who, when time permits, will information. The availability of a DBMS, however, offers users a much faster alternative communications patch (see figure). Special, direct, and other file processing approaches ate used to organize and structure data in single files. But a DBMS is able to integrate data elements from several files to answer specific user inquiries fir information. This means that the DBMS is able to structure and tie together the logically related data from several large files. Logical structures. Identifying these logical relationships is a job of the data administrator. A data definition language is used for this purpose. The DBMS may
Working with Databases This chapter describes how to use SQL statements in embedded applications to control databases. There are three database statements that set up and open databases for access: SET DATABASE declares a database handle, associates the handle with an actual database file, and optionally assigns operational parameters for the database. SET NAMES optionally specifies the character set a client application uses for CHAR, VARCHAR, and text Blob data. The server uses this information to transli terate from a database?s default character set to the client?s character set on SELECT operations, and to transliterate from a client application?s character set to the database character set on INSERT and UPDATE operations. g CONNECT opens a database, allocates system resources for it, and optionally assigns operational parameters for the database.All databases must be closed before a program ends. A database can be closed by using DISCONNECT, or by appending the RELEASE option to the final COMMIT or ROLLBACK in a program. Declaring a database Before a database can be opened and used in a program, it must first be declared with SET DATABASE to: CHAPTER 3 WORKING WITH DATABASES. Establish a database handle. Associate the database handle with a database file stored on a local or remote node.A database handle is a unique, abbreviated alias for an actual database name. Database handles are used in subsequent CONNECT, COMMIT RELEASE, and ROLLBACK RELEASE statements to specify which databases they should affect. Except in dynamic SQL (DSQL) applications, database handles can also be used inside transaction blocks to qualify, or differentiate, table names when two or more open databases contain identically named tables. Each database handle must be unique among all variables used in a program. Database handles cannot duplicate host-language reserved words, and cannot be InterBase reserved words.The following statement illustrates a simple database declaration:
管理信息系统外文翻译-标准化文件发布号：（9456-EUATWK-MWUB-WUNN-INNUL-DDQTY-KII
英文文献翻译 二〇年月日
科技文章摘译 Definition of a Management Information System There is no consensus of the definition of the term "management information system". Some writers prefer alternative terminology such as "information processing system", "information and decision system", "organizational information system", or simply "information system" to refer to the computer-based information processing system which supports the operations, management, and decision-making functions of an organization. This text uses “MIS” because it is descriptive and generally understood; it also frequently uses “information system” instead of “MIS” to refer to an organizational information system. A definition of a management information system, as the term is generally understood, is an integrated, user-machine system for providing information to support operations, management, and decision-making functions in an organization. The system utilizes computer hardware and software; manual procedures; models for analysis planning, control and decision making; and a database. The fact that it is an integrated system does not mean that it is a single, monolithic structure; rather, it means that the parts fit into an overall design. The elements of the definition are highlighted below. 1 Computer-based user-machine system Conceptually, management information can exist without computer, but it is the power of the computer which makes MIS feasible. The question is not whether computers should be used in management information system, but the extent to which information use should be computerized. The concept of a user-machine system implies that some tasks are best performed by humans, while others are best done by machine. The user of an MIS is any person responsible for entering input data, instructing the system, or utilizing the information output of the system. For many problems, the user and the computer form a combined system with results obtained through a set of interactions between the computer and the user. User-machine interaction is facilitated by operation in which the user’s input-output device (usually a visual display terminal) is connected to the computer. The computer can be a personal computer serving only one user or a large computer that
企业数据建模外文翻译文献 (文档含中英文对照即英文原文和中文翻译) 翻译： 信息系统开发和数据库开发 在许多组织中，数据库开发是从企业数据建模开始的，企业数据建模确定了组织数据库的范围和一般内容。这一步骤通常发生在一个组织进行信息系统规划的过程中，它的目的是为组织数据创建一个整体的描述或解释，而不是设计一个特定的数据库。一个特定的数据库为一个或多个信息系统提供数据，而企业数据模型（可能包含许多数据库）描述了由组织维护的数据的范围。在企业数据建模时，你审查当前的系统，分析需要支持的业务领域的本质，描述需要进一步抽象的数据，并且规划一个或多个数据库开发项目。图1显示松谷家具公司的企业数据模型的一个部分。 1.1 信息系统体系结构 如图1所示，高级的数据模型仅仅是总体信息系统体系结构(ISA)一个部分或一个组
织信息系统的蓝图。在信息系统规划期间，你可以建立一个企业数据模型作为整个信息系统体系结构的一部分。根据Zachman(1987)、Sowa和Zachman（1992）的观点，一个信息系统体系结构由以下6个关键部分组成: 数据（如图1所示，但是也有其他的表示方法）。 操纵数据的处理（着系可以用数据流图、带方法的对象模型或者其他符号表示）。 网络，它在组织内并在组织与它的主要业务伙伴之间传输数据（它可以通过网络连接和拓扑图来显示）。 人，人执行处理并且是数据和信息的来源和接收者（人在过程模型中显示为数据的发送者和接收者）。 执行过程的事件和时间点（它们可以用状态转换图和其他的方式来显示）。 事件的原因和数据处理的规则（经常以文本形式显示，但是也存在一些用于规划的图表工具，如决策表）。 1.2 信息工程 信息系统的规划者按照信息系统规划的特定方法开发出信息系统的体系结构。信息工程是一种正式的和流行的方法。信息工程是一种面向数据的创建和维护信息系统的方法。因为信息工程是面向数据的，所以当你开始理解数据库是怎样被标识和定义时，信息工程的一种简洁的解释是非常有帮助的。信息工程遵循自顶向下规划的方法，其中，特定的信息系统从对信息需求的广泛理解中推导出来（例如，我们需要关于顾客、产品、供应商、销售员和加工中心的数据），而不是合并许多详尽的信息请求（如一个订单输入屏幕或按照地域报告的销售汇总）。自顶向下规划可使开发人员更全面地规划信息系统，提供一种考虑系统组件集成的方法，增进对信息系统与业务目标的关系的理解，加深对信息系统在整个组织中的影响的理解。 信息工程包括四个步骤:规划、分析、设计和实现。信息工程的规划阶段产生信息系统体系结构，包括企业数据模型。 1.3 信息系统规划 信息系统规划的目标是使信息技术与组织的业务策略紧密结合，这种结合对于从信息系统和技术的投资中获取最大利益是非常重要的。正如表1所描述的那样，信息工程方法的规划阶段包括3个步骤，我们在后续的3个小节中讨论它们。 1.确定关键性的规划因素
数据库外文参考文献及翻译 数据库外文参考文献及翻译数据库管理系统——实施数据完整性一个数据库，只有用户对它特别有信心的时候。这就是为什么服务器必须实施数据完整性规则和商业政策的原因。执行SQL Server的数据完整性的数据库本身，保证了复杂的业务政策得以遵循，以及强制性数据元素之间的关系得到遵守。因为SQL Server的客户机/服务器体系结构允许你使用各种不同的前端应用程序去操纵和从服务器上呈现同样的数据，这把一切必要的完整性约束，安全权限，业务规则编码成每个应用，是非常繁琐的。如果企业的所有政策都在前端应用程序中被编码，那么各种应用程序都将随着每一次业务的政策的改变而改变。即使您试图把业务规则编码为每个客户端应用程序，其应用程序失常的危险性也将依然存在。大多数应用程序都是不能完全信任的，只有当服务器可以作为最后仲裁者，并且服务器不能为一个很差的书面或恶意程序去破坏其完整性而提供一个后门。SQL Server使用了先进的数据完整性功能，如存储过程，声明引用完整性（DRI），数据类型，限制，规则，默认和触发器来执行数据的完整性。所有这些功能在数据库里都有各自的用途;通过这些完整性功能的结合，可以实现您的数据库的灵活性和易于管理，而且还安全。声明数据完整性声明数据完整原文请找腾讯3249114六,维-论'文.网 https://www.doczj.com/doc/aa1840980.html, 定义一个表时指定构成的主键的列。这就是所谓的主键约束。SQL Server使用主键约束以保证所有值的唯一性在指定的列从未侵犯。通过确保这个表有一个主键来实现这个表的实体完整性。有时，在一个表中一个以上的列（或列的组合）可以唯一标志一行，例如，雇员表可能有员工编号（ emp_id ）列和社会安全号码（ soc_sec_num ）列，两者的值都被认为是唯一的。这种列经常被称为替代键或候选键。这些项也必须是唯一的。虽然一个表只能有一个主键，但是它可以有多个候选键。 SQL Server的支持多个候选键概念进入唯一性约束。当一列或列的组合被声明是唯一的， SQL Server 会阻止任何行因为违反这个唯一性而进行的添加或更新操作。在没有故指的或者合适的键存在时，指定一个任意的唯一的数字作为主键，往往是最有效的。例如，企业普遍使用的客户号码或账户号码作为唯一识别码或主键。通过允许一个表中的一个列拥有身份属性，SQL Server可以更容易有效地产生唯一数字。您使用的身份属性可以确保每个列中的值是唯一的，并且值将从你指定的起点开始，以你指定的数量进行递增（或递减）。（拥有特定属性的列通常也有一个主键或唯一约束，但这不是必需的。）第二种类型的数据完整性是参照完整性。 SQL Server实现了表和外键约束之间的逻辑关系。外键是一个表中的列或列的组合，连接着另一个表的主键（或着也可能是替代键）。这两个表之间的逻辑关系是关系模型的基础;参照完整性意味着这种关系是从来没有被违反的。例如，一个包括出版商表和标题表的简单的select例子。在标题表中，列title_id （标题编号）是主键。在出版商表，列pub_id （出版者ID ）是主键。 titles表还包括一个pub_id列，这不是主键，因为出版商可以发布多个标题。相反， pub_id是一个外键，它对应着出版商表的主键。如果你在定义表的时候声明了这个关系， SQL Server由双方执行它。首先，它确保标题不能进入titles表，或在titles表中现有的pub_id无法被修改，除非有效的出版商ID作为新pub_id出现在出版商表中。其次，它确保在不考虑titles表中对应值的情况下，出版商表中的pub_id的值不做任何改变。以下两种方法可
Enterprise Human Resources Management System Design And Implementation Abstract: Human resource management system is the core content of modern enterprise management. With the rapid development of the computer information technology and unprecedented prevalence of electronic commerce mode，the competition between enterprises is turning from visible economic markets to the network. Developing the human resource management system supported by computer technology，network technology and information technology can not only improve the skill of human resource management and the efficiency of the enterprises but also make human resource management modern and decision sciencefic,Modern human resource management uses B/S mode to avoid C/S modes short coming of difficult in maintdning and reusing.According to the functional requirements of the actual project,this article specificly state the analysis of system,the general desigin of the system,the detail design of system and the practice of the system. The development of the system is the practice of MVC design ideas, maing using the Jsp+Servlet+JavaBean form of development.Jsp is the practice of MVC design ideas’view,in charge of receiving/responding the request of the customer.Servlet mainly responsible for the core business control of the whole system is the practice of the vontroller of MVC design idea to take charge of the statistics and rules of the whole system. In the practice of the system, somr open-source projrcts,such as the Ajax technique,JfreChart statements,fileupload technology,has been used. Using the modern human resource management theropy and analysising the actual situation, comparing the current situation of human resource management system, a huaman resource contents of management system basied on the Internet/Intranet has been designed. The main management,attendance management training more efficient statistics. Keywords:human resource management; B/S mode; Open-source projects; MVC mode. 摘要 人力资源管理系统是现代企业管理的核心内容。随着计算机信息技术的高速发展，电子商务模式的空前盛行，企业之间的竞争也从有形的经济市场转向了网络。开发以计算机技术、网络技术、信息技术支持的现代人力资源管理系统，既能提高企业人力资源管理的技术含量和企业的办事效率，也能使人力资源管理能够进入现代化、决策科学化的进程。现代人力资源管理系统采用了B/S模式，可以避免C/S模式的重用性差、维护难度高的缺点和
英文翻译 数据库管理系统的介绍 Raghu Ramakrishnan 数据库（database,有时被拼作data base）又称为电子数据库，是专门组织起来的一组数据或信息，其目的是为了便于计算机快速查询及检索。数据库的结构是专门设计的，在各种数据处理操作命令的支持下，可以简化数据的存储、检索、修改和删除。数据库可以存储在磁盘、磁带、光盘或其他辅助存储设备上。 数据库由一个或一套文件组成，其中的信息可以分解为记录，每一条记录又包含一个或多个字段（或称为域）。字段是数据存取的基本单位。数据库用于描述实体，其中的一个字段通常表示与实体的某一属性相关的信息。通过关键字以及各种分类（排序）命令，用户可以对多条记录的字段进行查询，重新整理，分组或选择，以实体对某一类数据的检索，也可以生成报表。 所有数据库（除最简单的）中都有复杂的数据关系及其链接。处理与创建，访问以及维护数据库记录有关的复杂任务的系统软件包叫做数据库管理系统（DBMS）。DBMS软件包中的程序在数据库与其用户间建立接口。（这些用户可以是应用程序员，管理员及其他需要信息的人员和各种操作系统程序）DBMS可组织、处理和表示从数据库中选出的数据元。该功能使决策者能搜索、探查和查询数据库的内容，从而对正规报告中没有的，不再出现的且无法预料的问题做出回答。这些问题最初可能是模糊的并且（或者）是定义不恰当的，但是人们可以浏览数据库直到获得所需的信息。简言之，DBMS将“管理”存储的数据项和从公共数据库中汇集所需的数据项用以回答非程序员的询问。 DBMS由3个主要部分组成：（1）存储子系统，用来存储和检索文件中的数据；（2）建模和操作子系统，提供组织数据以及添加、删除、维护、更新数据的方法；（3）用户和DBMS之间的接口。在提高数据库管理系统的价值和有效性方面正在展现以下一些重要发展趋势： 1.管理人员需要最新的信息以做出有效的决策。 2.客户需要越来越复杂的信息服务以及更多的有关其订单，发票和账号的当前信息。
外文翻译： 索引 原文来源：Thomas Kyte．Expert Oracle Database Architecture ．2nd Edition． 译文正文： 什么情况下使用B*树索引? 我并不盲目地相信“法则”（任何法则都有例外），对于什么时候该用B*索引，我没有经验可以告诉你。为了证明为什么这个方面我无法提供任何经验，下面给出两种等效作法：?使用B*树索引，如果你想通过索引的方式去获得表中所占比例很小的那些行。 ?使用B *树索引，如果你要处理的表和索引许多可以代替表中使用的行。 这些规则似乎提供相互矛盾的意见，但在现实中，他们不是这样的，他们只是涉及两个极为不同的情况。有两种方式使用上述意见给予索引： ?作为获取表中某些行的手段。你将读取索引去获得表中的某一行。在这里你想获得表中所占比例很小的行。 ?作为获取查询结果的手段。这个索引包含足够信息来回复整个查询，我们将不用去查询全表。这个索引将作为该表的一个瘦版本。 还有其他方式—例如，我们使用索引去检索表的所有行，包括那些没有建索引的列。这似乎违背了刚提出的两个规则。这种方式获得将是一个真正的交互式应用程序。该应用中，其中你将获取其中的某些行，并展示它们，等等。你想获取的是针对初始响应时间的查询优化，而不是针对整个查询吞吐量的。 在第一种情况（也就是你想通过索引获得表中一小部分的行）预示着如果你有一个表T （使用与早些时候使用过的相一致的表T）,然后你获得一个像这样查询的执行计划： ops$tkyte%ORA11GR2> set autotrace traceonly explain ops$tkyte%ORA11GR2> select owner, status 2 from t 3 where owner = USER; Execution Plan ---------------------------------------------------------- Plan hash value: 1049179052 ------------------------------------------------------------------ | Id | Operation | Name | Rows | Bytes | ------------------------------------------------------------------ | 0 | SELECT STATEMENT | | 2120 | 23320 | | 1 | TABLE ACCESS BY INDEX ROWID |T | 2120 | 23320 | | *2 | INDEX RANGE SCAN | DESC_T_IDX | 8 | | ------------------------------------------------------------------ Predicate Information (identified by operation id): --------------------------------------------------- 2 - access(SYS_OP_DESCEND("OWNER")=SYS_OP_DESCEND(USER@!)) filter(SYS_OP_UNDESCEND(SYS_OP_DESCEND("OWNER"))=USER@!) 你应该访问到该表的一小部分。这个问题在这里看是INDEX (RANGE SCAN) 紧跟在
餐饮管理系统外文翻译文献(文档含中英文对照即英文原文和中文翻译) 英文： 1、China food industry development prospects analysis The catering industry in China as the tertiary industry is a traditional service industries, experienced reforming and opening starts, quantitative expansion, scale chain development and brand promotion strategy of 4phase, made make a spurt of progress in the development of. At present, the country has4 millions catering outlets. 2005/2006annual Chinese top 100 catering enterprises with total assets of about thirty-two billion yuan, total profit of about six billion yuan, employees about eight hundred thousand people, respectively, over the same period last year increased40.38%,28.84% and33.33% higher than that of the whole society, the catering industry average growth level. China's reform and opening up has gone through ups and downs in the30year, in the30 years of reforming and opening of China's catering industry along with the tide of reform has undergone three leap type development. In the past 30 years, China has experienced from fast food restaurants grabs beach China market to SARS impact, then to food safety ( tonyred event, apple events ), Chinese food and beverage industry in the impact, achieve sales growth.
河北工程大学毕业论文（设计）英文参考文献原文复印件及译文 数据仓库 数据仓库为商务运作提供结构与工具，以便系统地组织、理解和使用数据进行决策。大量组织机构已经发现，在当今这个充满竞争、快速发展的世界，数据仓库是一个有价值的工具。在过去的几年中，许多公司已花费数百万美元，建立企业范围的数据仓库。许多人感到，随着工业竞争的加剧，数据仓库成了必备的最新营销武器——通过更多地了解客户需求而保住客户的途 径。“那么”，你可能会充满神秘地问，“到底什么是数据仓库？” 数据仓库已被多种方式定义，使得很难严格地定义它。宽松地讲，数据仓库是一个数据库，它与组织机构的操作数据库分别维护。数据仓库系统允许将各种应用系统集成在一起，为统一的历史数据分析提供坚实的平台，对信息处理提供支持。 按照W. H. Inmon，一位数据仓库系统构造方面的领头建筑师的说法，“数 (1) 视图。 (2)
般文件和联机事务处理记录，集成在一起。使用数据清理和数据集成技术，确保命名约定、编码结构、属性度量的一致性等。 (3)时变的：数据存储从历史的角度（例如，过去5-10 年）提供信息。数据仓库中的关键结构，隐式或显式地包含时间元素。 (4) 非易失的：数据仓库总是物理地分离存放数据；这些数据源于操作环境下的应用数据。由于这种分离，数据仓库不需要事务处理、恢复和并行控制机制。通常，它只需要两种数据访问：数据的初始化装入和数据访问。 概言之，数据仓库是一种语义上一致的数据存储，它充当决策支持数据模型的物理实现，并存放企业决策所需信息。数据仓库也常常被看作一种体系结构，通过将异种数据源中的数据集成在一起而构造，支持结构化和启发式查询、分析报告和决策制定。 “好”，你现在问，“那么，什么是建立数据仓库？” 根据上面的讨论，我们把建立数据仓库看作构造和使用数据仓库的过程。数据仓库的构造需要数据集成、数据清理、和数据统一。利用数据仓库常常需要一些决策支持技术。这使得“知识工人”（例如，经理、分析人员和主管）能够使用数据仓库，快捷、方便地得到数据的总体视图，根据数据仓库中的信息做出准确的决策。有些作者使用术语“建立数据仓库”表示构造数据仓库的过程，而用术语“仓库DBMS”表示管理和使用数据仓库。我们将不区分二者。 “组织机构如何使用数据仓库中的信息？”许多组织机构正在使用这些信息支持商务决策活动，包括: (1)、增加顾客关注，包括分析顾客购买模式（如，喜爱买什么、购买时间、预算周期、消费习惯）； (2)、根据季度、年、地区的营销情况比较，重新配置产品和管理投资，调整生产策略； (3)、分析运作和查找利润源； (4)、管理顾客关系、进行环境调整、管理合股人的资产开销。 从异种数据库集成的角度看，数据仓库也是十分有用的。许多组织收集了形形色色数据，并由多个异种的、自治的、分布的数据源维护大型数据库。集成这些数据，并提供简便、有效的访问是非常希望的，并且也是一种挑战。数据库工业界和研究界都正朝着实现这一目标竭尽全力。 对于异种数据库的集成，传统的数据库做法是：在多个异种数据库上，建立一个包装程序和一个集成程序（或仲裁程序）。这方面的例子包括IBM 的数据连接程序和Informix的数据刀。当一个查询提交客户站点，首先使用元数据字典对查询进行转换，将它转换成相应异种站点上的查询。然后，将这些查询
毕业设计(论文)外文资料翻译设计(论文)题目图书管理系统 院系计算机工程系 专业计算机科学与技术 年级 学生学号1040520007 学生姓名bianhaiwei 外文出处CHINA-USA Business Review
Combining JSP and Servlets The technology of JSP and Servlet is the most important technology which use Java technology to exploit request of server, and it is also the standard which exploit business application .Java developers prefer to use it for a variety of reasons, one of which is already familiar with the Java language for the development of this technology are easy to learn Java to the other is "a preparation, run everywhere" to bring the concept of Web applications, To achieve a "one-prepared everywhere realized." And more importantly, if followed some of the principles of good design, it can be said of separating and content to create high-quality, reusable, easy to maintain and modify the application. For example, if the document in HTML embedded Java code too much (script), will lead the developed application is extremely complex, difficult to read, it is not easy reuse, but also for future maintenance and modification will also cause difficulties. In fact, CSDN the JSP / Servlet forum, can often see some questions, the code is very long, can logic is not very clear, a large number of HTML and Java code mixed together. This is the random development of the defects. Early dynamic pages mainly CGI (Common Gateway Interface, public Gateway Interface) technology, you can use different languages of the CGI programs, such as VB, C / C + + or Delphi, and so on. Though the technology of CGI is developed and powerful, because of difficulties in programming, and low efficiency, modify complex shortcomings,