CQL++ is a declarative front end to the Ode object-oriented database. It combines a SQL-like syntax with the C++ class model. CQL++ provides facilities for defining classes, and for creating, querying, displaying, and...
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Various proposals have been made to extend object-oriented languages and database systems with roles because they allow to weaken strict typing concepts and therefore can. provide mechanisms for an object to change it...
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ISBN:
(纸本)0769500846
Various proposals have been made to extend object-oriented languages and database systems with roles because they allow to weaken strict typing concepts and therefore can. provide mechanisms for an object to change its type during its lifetime. But this tie-called object migration is not the only advantage offered by a suitable role model. This paper studies the possibilities to use roles for a general change management system that also includes support for schema evolution. OPAQUE, as the selected role model, can be ea:tended with schema update mechanisms in a surprisingly clean and straightforward way including the concepts of versions and views as well.
A specific multiparadigm approach supporting both the object-oriented and the relational models in a unified database programming environment is presented. In addition to the relational facilities the environment supp...
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Deductive objectoriented database languages are faced with the problem of dealing with the new concepts of the objectoriented approach: object identity, inheritance, method, and complex object structure. Complex obj...
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ISBN:
(纸本)3540587861
Deductive objectoriented database languages are faced with the problem of dealing with the new concepts of the objectoriented approach: object identity, inheritance, method, and complex object structure. Complex object structures raise a consistency problem for derived objects. To the best of our knowledge, no method has been proposed to do a static check of the consistency of deductive programs dealing with complex objects. In this paper we propose a solution based on a deductive language, called ERCLog, for an object and relationship data model. ERCLog explicitly manages the cardinalities of the attributes of the objects and of the links between objects. This information allows the static checking of the consistency of the programs.
Knowledge discovery and data correlation require a unified approach to basic data management. However, achieving such an approach is nearly impossible with hundreds of disparate data sources, legacy systems and data f...
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ISBN:
(纸本)078037231X
Knowledge discovery and data correlation require a unified approach to basic data management. However, achieving such an approach is nearly impossible with hundreds of disparate data sources, legacy systems and data formats. This problem is pervasive in the space science community where data models, taxonomies and data management systems are locally implemented and limited metadata has been collected and organized. Technology developed by the objectoriented Data Technology (OODT) task at NASA's Jet Propulsion Laboratory (JPL) has been exploring component frameworks for managing, locating and exchanging data residing within a geographically distributed network. OODT has taken a novel approach towards solving this problem by exploiting web technologies usually dedicated to e-commerce, combined with a rich, metadata-based environment. The components developed by OODT create a set of distributed peer-to-peer services that allow for data managed by a peer to be searched and returned as part of an integrated data management system. This paper discusses the approach taken to develop a software framework, and two prototype development efforts for the Planetary Data System (PDS) and the Mission and Ground Asset Database.
作者：
Wu, XQISST
Fraunhofer Institute for Software Engineering and Systems Engineering Postfach 520130 44207 Dortmund Germany
As database technology advances rapidly, there are usually heterogeneous databases (hierarchical, relational or object-oriented databases) used by different departments in an enterprise. On the other hand, the object-...
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ISBN:
(纸本)354061656X
As database technology advances rapidly, there are usually heterogeneous databases (hierarchical, relational or object-oriented databases) used by different departments in an enterprise. On the other hand, the object-oriented technology is becoming the dominant application development paradigm. Thus, there is a data modeling gap between applications and heterogeneous databases. In this paper we present different architecture aspects of the system VHDBS1, which has been developed by an ongoing research project. This architecture provides a way to support cooperative access to distributed heterogeneous databases and to fill the data modeling gap in a distributed heterogeneous environment.
In this paper, we employ the view model given by Bertino to propose a new design approach for a secure multi-level object-oriented database system. The central idea is to provide the user with a multi-level view deriv...
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ISBN:
(纸本)3540619917
In this paper, we employ the view model given by Bertino to propose a new design approach for a secure multi-level object-oriented database system. The central idea is to provide the user with a multi-level view derived from a single-level secure object-oriented database. Hence the database operations performed on the multi-level views are decomposed into a set of operations on the single-level objects which can be implemented on any conventional mandatory security kernel. We show that this approach allows us to overcome the difficulties of handling content and context dependent classification, dynamic classification, and aggregation and inference problems in multi-level object-oriented databases.
Efficiently storing and retrieving archetype-based patient information can be a challenging task. This paper surveys current archetype-based system implementations in the world and in particular the different approach...
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ISBN:
(纸本)9781479910533
Efficiently storing and retrieving archetype-based patient information can be a challenging task. This paper surveys current archetype-based system implementations in the world and in particular the different approaches that have been used to create 13606- or openEHR-based storage repositories. Data is reported from systems with a few records to millions of records, including both deployed systems in production and experimental systems. Worldwide 21 projects were found, 4 did not reply and 1 did not provide data. Many systems (n=11) base their storage on RDBMS, then often (n=6) with some XML data fields. Dedicated XML (n=3) and object-oriented (n=2) databases were other examples of storage used. Query formalisms used include SQL, AQL, XQuery and XPath. Service interfaces via SOAP (n=12) or REST (n=6) are common. Most systems support dynamic configuration using new/changed archetypes and templates dynamically without system restart. Some (n=7) systems use demographic archetypes. In addition to the built in DBMS indexing mechanisms, one project reports use of an additional inverted index to achieve improved performance.
Data versioning is important for many applications such as CASE, CAD and CAM. New design objects in these applications are usually created from existing ones because they share a large degree of similarity. In this pa...
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ISBN:
(纸本)0818691832
Data versioning is important for many applications such as CASE, CAD and CAM. New design objects in these applications are usually created from existing ones because they share a large degree of similarity. In this paper, we propose a difference-based version model for object-oriented database systems. The large object is stored only the difference data from its parent version. To show the feasibility of this version model, a prototype is implemented and a performance study on the version storage and access time is made. We observe from this study that, when the difference between two versions is less than 10%, the system has the best storage efficiency and incurs the least overhead in access time. Our implementation experience also shows that the proposed version model can be implemented as an independent module to plug in a data storage system easily.
In this paper, a parallel retrieving scheme of complex objects' index is described in a objectoriented database framework. We handle complex queries, which include simple queries combined by AND, OR, NOT logical ...
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ISBN:
(纸本)1880843463
In this paper, a parallel retrieving scheme of complex objects' index is described in a objectoriented database framework. We handle complex queries, which include simple queries combined by AND, OR, NOT logical operators. Our scheme employs the multiindexing technique, and complex queries are normalized to avoid the retrieval redundancies. We provide an effective retrieval method combined with incorporated algorithms to detect the set operation termination.
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