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.thingsB.objectsC.conditionsD.constrains
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
B.objects
C.conditions
D.constrains
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解析：
相关考题：
● 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 dictionaryB．dataflow diagramC．use case diagramD．entity-relationship diagram
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
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 dictionaryB．dataflow diagramC．use case diagramD．entity-relationship diagram
● 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 decompositionB. object abstractionC. data inheritanceD. information generalization（72）A. function model，class model and state modelB. class model，interaction model and state modelC. class model，interaction model and sequence modelD. function model，interaction model and state model（73）A. Static analysisB. Semantic analysisC. Scope analysisD. Domain analysis（74）A. static structureB. system componentsC. data flowsD. program procedures（75）A. Program analysisB. Function requirementC. Application analysisD. Physical model
____________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 wordB、A cognitive meaning of a wordC、Denotative meaning of a word or a lexical itemD、Collocations
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．PrototypingB．AcceleratedC．Model-drivenD．Iterative
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．ProgrammingB．AnalyzingC．DesigningD．Modeling
The basic concept of a data(72)is the difference between data and information.A．warehouseB．storageC．baseD．service
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．toolB．inC．ideaD．contributionE．real-world
（ ）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
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 the analysis model are (72) ．There are two substages of object-oriented analysis． (73) focuses on real-world things whose semantics the application captures．The object constructed in the requirement analysis shows the (74) of the real-world system and organizes it into workable pieces． (75) addresses the computer aspects ofthe application that are visible to users．The objects are those which can be expected to vary from time to time quite rapidly．（71）A．functional decompositionB．object abstractionC．data inheritanceD．information generalization
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（请作答此空），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（ ）to which thecontents of a database must conform.The entity-relationship model is widely used in database design.A.dataB.thingsC.entitiesD.objects
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（请作答此空）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.static structureB.system componentsC.data flowsD.program procedures
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.（请作答此空）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.Program analysisB.Function requirementC.Application analysisD.Physical model
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.（请作答此空）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.Static analysisB.Semantic analysisC.Scope analysisD.Domain analysis
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（请作答此空）.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.function model，class model and state modelB.class model，interaction model and state modelC.class model，interaction model and sequence modelD.function model，interaction model and state model
System analysis is traditionally done top-down using structured analysis based on____.Object-oriented analysis focuses on creation of models.The three types of the analysis model are___.There are two substages of object-oriented analysis.__请作答次选项__focuses on real-world things whose semantics the application captures.The object constructed in the requirement analysis shows the____of the real-world system and organizes it into workable pieces.____addresses the computer aspects of the application that are visible to users.The objects are those which can be expected to vary from time to time quite rapidly.A.Static analysisB.Semantic analysisC.Scope analysisD.Domain analysis
System analysis is traditionally done top-down using structured analysis based on____.Object-oriented analysis focuses on creation of models.The three types of the analysis model are____.There are two substages of object-oriented analysis.____focuses on real-world things whose semantics the application captures.The object constructed in the requirement analysis shows the___of the real-world system and organizes it into workable pieces.__请作答该选项__addresses the computer aspects of the application that are visible to users.The objects are those which can be expected to vary from time to time quite rapidly.A.Program analysisB.Function requirementC.Application analysisD.Physical model
System analysis is traditionally done top-down using structured analysis based on____.Object-oriented analysis focuses on creation of models.The three types of the analysis model are__请作答此选项__.There are two substages of object-oriented analysis.____focuses on real-world things whose semantics the application captures.The object constructed in the requirement analysis shows the____of the real-world system and organizes it into workable pieces.____addresses the computer aspects of the application that are visible to users.The objects are those which can be expected to vary from time to time quite rapidly.A.function model,class model and state modelB.class model,interaction model and state modelC.class model,interaction model and sequence modelD.function model,interaction model and state model
（ ） 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
Given that Thing is a class， how many objects and reference variables are created by the following code？（） Thing item， stuff； item = new Thing（）； Thing entity = new Thing（）；A、One object is createdB、Two objects are createdC、Three objects are createdD、One reference variable is createdE、Two reference variables are createdF、Three reference variables are created.
A customer asked a consultant to create the infrastructure for an application. The application is designed to charge customers for conferencing services based on usage. To determine if a Storage Area Network （SAN） is the best storage solution， which of the following questions is most appropriate？（）A、Will the application require a database？B、Which operating system does the application require？C、Will the data need to be backed up in real time？D、Does the application share data among the servers？
Which statement is true？（）A、A class’s finalize（） method CANNOT be invoked explicitly.B、super.finalize（） is called implicitly by any overriding finalize（） method.C、The finalize（） method for a given object is called no more than once by the garbage collector.D、The order in which finalize（） is called on two objects is based on the order in which the two objects became finalizable.
单选题A customer asked a consultant to create the infrastructure for an application. The application is designed to charge customers for conferencing services based on usage. To determine if a Storage Area Network （SAN） is the best storage solution， which of the following questions is most appropriate？（）AWill the application require a database？BWhich operating system does the application require？CWill the data need to be backed up in real time？DDoes the application share data among the servers？
多选题Which two are true？（）AA finalizer may NOT be invoked explicitly.BThe finalize method declared in class Object takes no action.Csuper.finalize（）is called implicitly by any over riding finalize method.DThe finalize method for a given objec twill be called no more than once by the garbage collector.EThe order in which finalize will be called on two objects is based on the order in which the two objects became finalizable.
单选题Which statement is true？（）AA class’s finalize（） method CANNOT be invoked explicitly.Bsuper.finalize（） is called implicitly by any overriding finalize（） method.CThe finalize（） method for a given object is called no more than once by the garbage collector.DThe order in which finalize（） is called on two objects is based on the order in which the two objects became finalizable.
多选题Given that Thing is a class， how many objects and reference variables are created by the following code？（） Thing item， stuff； item = new Thing（）； Thing entity = new Thing（）；AOne object is createdBTwo objects are createdCThree objects are createdDOne reference variable is createdETwo reference variables are createdFThree reference variables are created.