共查询到17条相似文献,搜索用时 125 毫秒
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UML是目前面向对象分析设计中的一种标准建模技术,它被用作确定、构建和文档化一个系统的结构.本文主要探讨以UML对象类图为中心出发点,来为数据库建模的方法:在UML的对象类中得到关系模式的键;把关联的多重性分配到关系模式中去;把泛化(继承)联系转换为关系模式;把行为(操作)转换为触发器和存储过程. 相似文献
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UML被MDA用来描述各种模型,成为建模语言事实上的标准。但是,由于UML类图中缺少对关系数据库的实现的约束,使得类图转换到的关系数据库模型不唯一,不能充分体现设计者对数据库的设计意图。这不利于MDA中PIM模型和关系PSM模型的双向转换。为解决以上问题,本文提出一种通过添加构造型和OCL约束来扩展UML类图的方法,以加强类图中数据之间的关系及约束,使PIM模型能够唯一地转换到PSM模型。最后,采用QVT模型转换方法将扩展后的UML类图转换到关系数据库模型,并结合例子给出了UML类图的关联、继承、组合和聚合关系等到关系数据库模型的转换规则和方法。利用本方法可以使UML类图到关系数据库模型的转换结果唯一。 相似文献
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UML模型一致性自动检测的主要任务是解决形式化问题。描述逻辑是一阶谓词逻辑的可判定子集,具备强大的知识表示和推理功能。针对UML模型形式化问题,提出基于描述逻辑的形式化方法,分析UML类图各模型元素与描述逻辑SHOIN(D)的对应关系,提出UML类图的SHOIN(D)形式化方法,给出UML类图转换为SHOIN(D)知识库的正确性证明。 相似文献
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基于形式化UML的教务管理数据库实现方法 总被引:1,自引:1,他引:1
利用统一建模语言(UML),实现了从高校教务管理类模式向教务管理关系数据库数据模式的转换.首先,以学籍管理系统为例,用UML的用例图、序列图、类图对其进行了建模.然后,在类的设计过程中,借助面向度量的UML的代数表达框架,检测了一些类模式的设计错误,对类模式进行了一些优化.最后,运用类图中类间的几种关系在关系数据库中的实现策略,建立了学籍管理数据库中的表. 相似文献
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UML在数据库建模中的应用 总被引:8,自引:0,他引:8
文章以煤层自然发火管理信息系统数据库建模为例,讨论将UML类图映射成关系型数据库中的表的方法,并对煤层自然发火管理信息系统数据库的关系模式进行了规范化。 相似文献
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分析UML模型一致性检测的研究意义,以及UML类图推理的研究现状,提出一种基于OWL本体的UML类图推理方案.研究UML类图向OWL本体转换的映射规则,给出UML类图包含关系、可满足性、等价关系和相离关系的判断方法及其推理规则.利用Jena推理机制实现了UML类图包含关系、可满足性、等价关系和相离关系的推理. 相似文献
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统一建模语言(UML)是一个半形式化的语言,其语义部分是采用自然语言描述的,使得它在建模过程中会产生语义不一致等问题。在详细比较UML类图与本体的基础上,提出了一种UML类图的形式化方法;首先将UML类图转换为相应的本体;然后根据本体提供的推理算法(Tableau)对转换得到的本体进行推理,检测其中的不一致性从而修改UML类图,最后达到精确UML类图。 相似文献
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额尔敦陶克素 《计算机工程与设计》2008,29(5):1279-1282
UML作为一种面向对象的标准建模语言,在关系数据库系统的建模领域也得到了广泛的应用.用UML为关系数据库模式建立的模型比ER模型表达力更强,但目前的UML数据库建模技术主要强调静态模型.概述了如何使用UML动态建模方法为关系数据库操作建模.在建立的框架的基础上可为原子数据库操作建模,进而为更复杂的数据库操作建模.这种方法将为用户和开发者提供对整个系统的一个统一视角,将UML的强大功能扩展到数据库领域. 相似文献
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《Information and Software Technology》1999,41(5):275-281
When transforming relational database (RDB) schema into object-oriented database(OODB) schema, much effort was put on examining key and inclusion dependency (ID) constraints to identify class and establish inheritance and association between classes. However, in order to further remove the original data redundancy and update anomaly, multi-valued dependency (MVD) should also be examined. In this paper, we discuss class structures and define well-structured classes. Based on MVDs, a theorem is given transforming a relation schema into a well-structured class. To transform RDB schema into OODB schema, a composition process simplifying the input RDB schema and an algorithm transforming the simplified RDB schema into well-structured OODB classes are developed. 相似文献
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XML has become the standard for publishing and exchanging data on the Web. However, most business data is managed and will
remain to be managed by relational database management systems. As such, there is an increasing need to efficiently and accurately
publish relational data as XML documents for Internet-based applications. One way to publish relational data is to provide
virtual XML documents for relational data via an XML schema which is transformed from the underlying relational database schema
such that users can access the relational database through the XML schema. In this paper, we discuss issues in transforming
a relational database schema into the corresponding XML schema. We aim to preserve all integrity constraints defined in a
relational database schema, to achieve high level of nesting and to avoid introducing data redundancy in the transformed XML
schema. In the paper, we first propose a basic transformation algorithm which introduces no data redundancy, then we improve
the algorithm by exploring further nesting of the transformed XML schema. 相似文献
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Data transformation is the core process in migrating database from relational database to NoSQL database such as column-oriented database. However,
there is no standard guideline for data transformation from relational database to
NoSQL database. A number of schema transformation techniques have been proposed to improve data transformation process and resulted better query processing
time when compared to the relational database query processing time. However,
these approaches produced redundant tables in the resulted schema that in turn
consume large unnecessary storage size and produce high query processing time
due to the generated schema with redundant column families in the transformed
column-oriented database. In this paper, an efficient data transformation technique
from relational database to column-oriented database is proposed. The proposed
schema transformation technique is based on the combination of denormalization
approach, data access pattern and multiple-nested schema. In order to validate the
proposed work, the proposed technique is implemented by transforming data from
MySQL database to HBase database. A benchmark transformation technique is
also performed in which the query processing time and the storage size are compared. Based on the experimental results, the proposed transformation technique
showed significant improvement in terms query processing time and storage space
usage due to the reduced number of column families in the column-oriented
database. 相似文献
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The most common way of designing databases is by means of a conceptual model, such as E/R, without taking into account other
views of the system. New object-oriented design languages, such as UML (Unified Modelling Language), allow the whole system,
including the database schema, to be modelled in a uniform way. Moreover, as UML is an extendable language, it allows for
any necessary introduction of new stereotypes for specific applications. Proposals exist to extend UML with stereotypes for
database design but, unfortunately, they are focused on relational databases. However, new applications require complex objects
to be represented in complex relationships, object-relational databases being more appropriate for these requirements. The
framework of this paper is an Object-Relational Database Design Methodology, which defines new UML stereotypes for Object-Relational
Database Design and proposes some guidelines to translate a UML conceptual schema into an object-relational schema. The guidelines
are based on the SQL:1999 object-relational model and on Oracle8i as a product example.
Initial submission: 22 January 2002 / Revised submission: 10 June 2002
Published online: 7 January 2003
This paper is a revised and extended version of Extending UML for Object-Relational Database Design, presented in the UML’2001
conference [17]. 相似文献
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本文介绍了基于Smith图的计算机辅助数据库设计的基础理论和由Smith图合成规范化关系模式的合成法则,给出了一个定理并证明了由合成法则得到的关系模式是完全规范化的。 相似文献
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UML类图是UML建模语言的核心元素之一,类图模型的正确性和一致性对于保证需求分析的正确性至关重要。论文研究了UML类图模型的语义一致性问题,提出了一种自动检验类图一致性的方法。该方法以扩展的关系逻辑为语义基础,把一致性问题归结为关系逻辑公式的可满足性问题。实践表明,该方法能够有效的检查UML类图模型的一致性,发现需求分析中的错误和漏洞,在一定程度上保证了类图模型的正确性。 相似文献