XML has become the standard for publishing and exchanging data on the Web. Since most of the business data nowadays are stored in structured databases including relational and object-oriented databases (OODB), it is o...
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XML has become the standard for publishing and exchanging data on the Web. Since most of the business data nowadays are stored in structured databases including relational and object-oriented databases (OODB), it is of significance to automate the transformation process and generate the XML data containing information from existing databases. At the same time, information imprecision and uncertainty exist in many practical applications, and for this reason, fuzzy data modeling has been extensively investigated in various data models. As such, there is an increasing need to effectively publish fuzzy structured data as fuzzy XML documents for Web-based applications. In this paper, we take a significant step in a fundamental consolidation of fuzzy XML. In particular, we are interested in finding an XML schema that best describes the existing fuzzy object-oriented schema. To accomplish this, we first offer mapping formalisms to capture the semantics of fuzzy XML Schema and fuzzy object-oriented schema. To allow for better and platform independent sharing of data stored in an object-oriented format, we investigate the formal transformation from fuzzy OODB to fuzzy XML and develop a set of rules to assist in the transformation process.
The paper is concerned with the problem of combining deductive and object-oriented features to produce a deductive object-oriented database system which is comparable to those currently available under the relational ...
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The paper is concerned with the problem of combining deductive and object-oriented features to produce a deductive object-oriented database system which is comparable to those currently available under the relational view of data modelling not only in its functionality but also in the techniques employed in its construction and use. Under this assumption, the kinds of issues that have to be tackled for a similar research strategy to produce comparable results are highlighted. The authors motivate their terms of comparison, characterize three broad approaches to deductive object-oriented databases and introduce the notion of language convergence to help in the characterization of some shortcomings that have been perceived in them. Three proposals that have come to light in the past three years are looked into in some detail, in so far as they exemplify some of the positions in the space of choices defined. The main contribution of the paper is towards a characterization of the language convergence property of deductive database languages which has a key role in addressing critiques of the deductive and object-oriented database research enterprise. A basic familiarity with notions from deductive databases and from object-oriented databases is assumed.
Conventional object-oriented database (OODB) systems follow a class-based approach to model real world entities and their relationships, which imposes several difficulties when more advanced "dynamic functions&qu...
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Conventional object-oriented database (OODB) systems follow a class-based approach to model real world entities and their relationships, which imposes several difficulties when more advanced "dynamic functions" are needed by the applications. One of such dynamic functions is conceptual clustering - the ability to dynamically group a set of existing objects together as a higher-level abstract object (called a "cluster"). The conceptual clustering model (CCM) that we have defined is an extension to current object-oriented models, which facilitates the modeling of dynamic, evolving, and/or ad hoc object clusters through a well-devised clustering mechanism that incorporates "roles". This paper presents the advanced features of CCM, along with its associated query language facilities devised for supporting general definition and access of clusters (and roles). An experimental prototype of the CCM has been constructed on top of a persistent object storage manager, running on a Sun4 workstation.
The Resource Description Framework and RDF Schema recommended by the World Wide Web Consortium provide a flexible model for semantically representing information about resources on the Web, which are playing an increa...
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The Resource Description Framework and RDF Schema recommended by the World Wide Web Consortium provide a flexible model for semantically representing information about resources on the Web, which are playing an increasingly important role in intelligent processing of large-scale data. With the widespread acceptance and applications of RDF(S), construction of RDF(S) is of increasing importance. Automatic construction of RDF(S) with diverse data has attracted more attention. In this paper, we propose a novel approach for constructing an RDF(S) with object-oriented databases that are suitable for non-traditional applications. We propose the formal rules of mapping an object-oriented database model into a RDF(S) model based on the formal definitions of these two models. We develop a tool named OODB2RDF to verify our approach.
The problem of access differentiation in generic object-oriented databases is investigated. Aspects of data processing and access control in databases are considered.
The problem of access differentiation in generic object-oriented databases is investigated. Aspects of data processing and access control in databases are considered.
We present a theorem-prover based analysis tool for object-oriented database systems with integrity constraints. object-oriented database specifications are mapped to higher-order logic (HOL). This allows us to reason...
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ISBN:
(纸本)3540657037
We present a theorem-prover based analysis tool for object-oriented database systems with integrity constraints. object-oriented database specifications are mapped to higher-order logic (HOL). This allows us to reason about the semantics of database operations using a mechanical theorem prover such as Isabelle or PVS. The tool can be used to verify various semantics requirements of the schema (such as transaction safety, compensation, and commutativity) to support the advanced transaction models used in workflow and cooperative work. We give an example of method safety analysis for the generic structure editing operations of a cooperative authoring system.
In this paper a semantic approach for the specification and the management of databases with evolving schemata is introduced. It is shown how a general object-oriented model for schema versioning and evolution can be ...
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ISBN:
(数字)9783540449577
ISBN:
(纸本)3540677976
In this paper a semantic approach for the specification and the management of databases with evolving schemata is introduced. It is shown how a general object-oriented model for schema versioning and evolution can be formalized;how the semantics of schema change operations can be defined;how interesting reasoning tasks can be supported, based on an encoding in description logics.
This paper deals with modelling constraints in object-oriented databases, with emphasis given on exceptions. Constraints are restrictions on properties and relations of database objects that ensure the integrity of da...
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ISBN:
(纸本)3540587861
This paper deals with modelling constraints in object-oriented databases, with emphasis given on exceptions. Constraints are restrictions on properties and relations of database objects that ensure the integrity of data. Therefore, they should be obeyed by every object, but as in real-life, there are some exceptions to this ruler object-oriented databases provide rich semantic constructs, adequate to model real-world relations. Inheritance of constraints in object-oriented databases has been treated in a completely mandatory way, providing no room for exceptions. In this paper, an object-oriented constraint representation scheme is presented, along with a methodology for modelling constraint exceptions. Finally, an algorithm is described that ensures correct runtime resolution of constraint applicability. Since business is not in abstract, but in real-world, business database modelling would be greatly benefited from a tool that allows both a clear definition and an efficient enforcement of constraints with exceptions.
In this paper, based on possibility distribution and the semantic measure of fuzzy data, we investigate subclass-superclass relationships in the fuzzy object-oriented databases. We identify fuzzy class and develop sof...
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ISBN:
(纸本)9780769536798
In this paper, based on possibility distribution and the semantic measure of fuzzy data, we investigate subclass-superclass relationships in the fuzzy object-oriented databases. We identify fuzzy class and develop soft computing methods in the paper to quantitatively determine the fuzzy subclass-superclass *** strategies to resolve the conflicts in multiple inheritance of class are also presented.
The paper focuses on the indexing on non-primitive (complex) values of attributes in an object management system. A new index structure for indexing on set (multivalued) attributes is proposed. This structure is based...
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ISBN:
(纸本)0818681306
The paper focuses on the indexing on non-primitive (complex) values of attributes in an object management system. A new index structure for indexing on set (multivalued) attributes is proposed. This structure is based an a partial order imposed on the values of the indexed attribute, which are subsets of a set of primitive values. It is shown that the proposed index allows the system to efficiently perform typical set operators that are postulated to be applied in object query languages (is-equal, is-subset, is-superset), without performing any costly operations on lists of object identifiers that would be necessary in traditional index structures. The new index structure called partial-order tree, is described and algorithms performing the set operators are outlined.
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