The entity-relationship(E-R)data model is based on a perception of a real world that consists of a clletion of basic objects,called( ),and of relationships among these objects.An entity is a“thing”or

题目
The entity-relationship(E-R)data model is based on a perception of a real world that consists of a clletion of basic objects,called( ),and of relationships among these objects.An entity is a“thing”or"object"in the real world that is distinguishable from other objects.Entities are described in a database by asetof( ):A relationship isan association among several entities.The set of all entities of the same type and the set of all relationships of the ametype are termed an entity sct and relationship set,respectively.The overall logical structure(schema)of a database can be expressed graphically by an E-R diagram,which is built up from the fllowing components:( )represent entity set,( )represent atributes,ete.In addition to entities and relations,the E-R model represents certain(请作答此空)to which thecontents of a database must conform.The entity-relationship model is widely used in database design.

A.things
B.objects
C.conditions
D.constrains
参考答案和解析
答案:D
解析:
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相似问题和答案

第1题:

One tool that is useful during both analysis and design is the ______,which is a pictorial representation of the items of infonnation(entities)within the system and the relationships between these pieces of information.

A.data dictionary

B.dataflow diagram

C.use case diagram

D.entity-relationship diagram


正确答案:D
解析:在系统分析和设计中同样适用的工具是答案D实体关系图,它通过图形形式,表现系统内的实体信息以及这些信息之间的关系。

第2题:

____________refers to those words that we use to label things as regards real objects, such as a name or a sign, etc, in the physical world.

A、A connotative meaning of a word

B、A cognitive meaning of a word

C、Denotative meaning of a word or a lexical item

D、Collocations


参考答案:C

第3题:

● One tool that is useful during both analysis and design is the (72) ,which is a pictorial representation of the items of information(entities) within the system and the relationships between these pieces of information.

(72)

A.data dictionary

B.dataflow diagram

C.use case diagram

D.entity-relationship diagram


正确答案:D
试题(72)分析
    在系统分析和设计中同样适用的工具是答案D实体关系图,它通过图形形式,表现系统内的实体信息以及这些信息之间的关系。
参考答案
    (72)D

第4题:

Object-oriented DBMS integrated a variety of(81)data types-such as business procedures, graphics, pictures, voice and annotated text.Object orientation also makes a(82)to application development efficiency. It makes the data, functions, attributes, and relationships an integral part of the(83). In this way, objects can be reused and replicated.Some leading RDBMS vendors support the concept of integrating object management capabilities with their current line of relational products. That capability enable users to the development cycle, since integrity logic and business roles no longer need to be programmed(84)each application.

A.tool

B.in

C.idea

D.contribution

E.real-world


正确答案:E

第5题:

It should go without saying that the focus of UML is modeling. However, what that means, exactly, can be an open-ended question.(71)is a means to capture ideas, relationships, decisions, and requirements in a well-defined notation that can be applied to many different domains. Modeling not only means different things to different people, but also it can use different pieces of UML depending on what you are trying to convey. In general, a UML model is made up of one or more(72)A diagram graphically represents things, and the relationships between these things. These(73)can be representations of real-world objects, pure software constructs, or a description of the behavior. of some other objects. It is common for an individual thing to show up on multiple diagrams; each diagram represents a particular interest, or view, of the thing being modeled. UML 2.0 divides diagrams into two categories: structural diagrams and behavioral diagrams.(74)are used to capture the physical organization of the things in your system, i.e., how one object relates to another.(75)focus on the behavior. of elements in a system. For example, you can use behavioral diagrams to capture requirements, operations, and internal state changes for elements.

A.Programming

B.Analyzing

C.Designing

D.Modeling


正确答案:D
解析:UML的核心关注内容是建模,而建模是一个开放性的问题。建模是采用合适并预先定义的符号来描述捕获的思想、关系、决策和需求,并且建模可应用到多个领域。建模对不同的人有不同的含义,可以使用UML中不同的部分来描述你所要涵盖的内容。一般来说,UML模型是由一个或者多个diagram组成。一个diagram使用图形化的方式描述了事物以及事物之间的关系,而事物代表了真实世界中的对象、软件构件或对象行为。常常一个独立的事物会在多个diagram中展现,每个diagram建模了该事物的不同方面。UML 2.0将diagram分为两大类:结构化diagram和行为diagram。结构化diagram主要用于捕获系统的物理组织结构,如一个对象与其他对象的关系。行为diagram则用于捕获需求、操作以及元素内部状态的变化。

第6题:

● System analysis is traditionally done top-down using structured analysis based on (71). Object-oriented analysis focuses on creation of models. The three types of theanalysis model are (72). There are two substages of object-oriented analysis. (73) focuses on real-world things whose semantics the application captures. The object constructedin the requirement analysis shows the (74) of the real-world system and organizes it intoworkable pieces.(75)addresses the computer aspects of the application that are visible tousers. The objects are those which can be expected to vary from time to time quite rapidly.

(71)

A. functional decomposition

B. object abstraction

C. data inheritance

D. information generalization

(72)

A. function model,class model and state model

B. class model,interaction model and state model

C. class model,interaction model and sequence model

D. function model,interaction model and state model

(73)

A. Static analysis

B. Semantic analysis

C. Scope analysis

D. Domain analysis

(74)

A. static structure

B. system components

C. data flows

D. program procedures

(75)

A. Program analysis

B. Function requirement

C. Application analysis

D. Physical model


正确答案:A,B,D,A,C
参考译文
传统的系统分析以功能分解为基础,利用结构化分析自顶向下完成。面向对象分析关注于模型的创建。该分析模型有三种类型:类模型、交互模型和状态模型。面向对象分析有两个子阶段。领域分析侧重于现实世界中那些语义被应用程序获取的事物。在需求分析中所构造的对象说明了现实世界系统的静态结构并将其组织为可用的片段。应用分析处理应用系统中用户可见的计算机问题。所分析的对象可能会被预计时不时地发生较快的变化。
参考答案
(71)A  (72)B(73)D(74)A(75)C

第7题:

analysis emphasizes the drawing of pictorial system models to document and validate both existing and/or proposed systems. Ultimately, the system models become the(72)for designing and constructing an improved system.(73)is such a technique. The emphasis in this technique is process-centered. Systems analysts draw a series of process models called(74).(75)is another such technique that integrates data and process concerns into constructs called objects.

A.Prototyping

B.Accelerated

C.Model-driven

D.Iterative


正确答案:C

第8题:

System analysis is traditionally done top-down using structured analysis based on( ). Object-oriented analysis focuses on creation of models. The three types of theanalysis model are( ). There are two substages of object-oriented analysis.( )focuses on real-world things whose semantics the application captures. The object constructedin the requirement analysis shows the( )of the real-world system and organizes it intoworkable pieces.( )addresses the computer aspects of the application that are visible tousers. The objects are those which can be expected to vary from time to time quite rapidly.

A.functional decomposition B.object abstraction C.data inheritance D.information generalization A.function model,class model and state model B.class model,interaction model and state model C.class model,interaction model and sequence model D.function model,interaction model and state model A.Static analysis B.Semantic analysis C.Scope analysis D.Domain analysis A.static structure B.system components C.data flows D.program procedures A.Program analysis B.Function requirement C.Application analysis D.Physical model


正确答案:A,B,D,A,C

第9题:

The basic concept of a data(72)is the difference between data and information.

A.warehouse

B.storage

C.base

D.service


正确答案:A
解析:数据仓库的基本概念就是数据和信息的不同。

第10题:

( )is used to model aggregates of information and the relationships these aggregates have to other.

A.Data flow diagram B.Entity relationship diagram C.Sequence diagram D.Structure diagram


正确答案:B

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