作者：
Myers, A.C.MIT
Laboratory for Computer Science 545 Technology Square CambridgeMA02139 United States
It is argued that future applications will require integrity of complex, persistent data in the face of hardware and program failures. We discuss Thor, a new object-oriented database, which offers a computational mode...
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The object-oriented data model TM is a language that is based on the formal theory of FM, a typed language with object-oriented features such as attributes and methods in the presence of subtyping. The general (typed)...
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Much of the research in security for object-oriented databases follows the traditional lines of discretionary access control, mandatory access control, and multilevel secure database systems. In this position paper, o...
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In this paper an approach of objectoriented database for an open energy management system is introduced. The requirement of an open system and the merit of the objectoriented programming technique are briefly descri...
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ISBN:
(纸本)780003285X
In this paper an approach of objectoriented database for an open energy management system is introduced. The requirement of an open system and the merit of the objectoriented programming technique are briefly described. An example of objectoriented database design is proposed.
The semantics of objects and transactions in database systems are investigated. User-defined predicates called consistency assertions are used to specify user programs. Three new correctness criteria are proposed. The...
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The semantics of objects and transactions in database systems are investigated. User-defined predicates called consistency assertions are used to specify user programs. Three new correctness criteria are proposed. The first correctness criterion consistency is based solely on the users' specifications and admits nonserializable executions that are acceptable to the users. Integrity constraints of the database are maintained through consistency assertions. The second correctness criterion orderability is a generalization of view serializability and represents a weak notion of equivalence to a serial schedule. Finally, the third correctness criterion strong orderability is introduced as a generalization of conflict serializability. Unlike consistency, the notions of orderability allow users to operate in isolation as maintenance of the integrity constraints now becomes the responsibility of the database system.
In a network of autonomous cooperating agents, complex distributed objects can be shared and exchanged. The novel feature presented in this paper is handling complex distributed objects, that we claim to be essential ...
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In a network of autonomous cooperating agents, complex distributed objects can be shared and exchanged. The novel feature presented in this paper is handling complex distributed objects, that we claim to be essential for cooperating teams of engineers e.g. in CIM, and in an environment that supports the integration of a group of expert systems. A model is presented here for the creation, retrieval, and modification of complex objects that are distributed in a federation of cooperating agents. The information that agents are willing to share with others in the federation is uniformly represented as inter-related objects. This defines a distributed object graph that spans over the entire federation of agents. Complex objects form a connected subgraph of this distributed object graph. To support safe cooperation and sharing of complex objects, while preserving agents’ autonomy, agents can bilaterally negotiate the access rights and deletion policies on distributed complex objects and when necessary these rights are propagated. Since the access rights are negotiated among agents, and not imposed by a central authority, the autonomy of each agent is fully maintained. To enable application programs to define and retrieve a complex object as a single entity, a linearization mechanism is introduced in the paper. The model described here has been developed as a part of the PEER system. PEER is a federated objectbase, designed and implemented as part of the Archon abstract machine, which provides an environment for the integration of heterogeneous cooperating expert systems.
DBface is a toolkit for designing interfaces to object-oriented databases. It provides users with a set of tools for building custom interfaces with minimal programming. This is accomplished by combining techniques fr...
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DBface is a toolkit for designing interfaces to object-oriented databases. It provides users with a set of tools for building custom interfaces with minimal programming. This is accomplished by combining techniques from User Interface Management Systems (UIMS) with a built-in knowledge about the specific kinds of techniques used by object-oriented databases. DBface allows users to create graphical constructs and interactive techniques by taking advantage of an object-oriented database environment and tools. Not only can database tools be used for creating an interface, but information about the interface being built is stored within a database schema and is syntactically consistent with all other schema information. Thus, an interface can deal with data and schema information, including information about another interface. This allows for easy reusability of graphical constructs such as data representations.
This talk will outline the principles, the architecture and the potential target applications of a Deductive and object-oriented Database System (DOOD). Such systems combine the novel functionalities (relying on the a...
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object-oriented database systems (OODBs) need efficient support for manipulation of complex objects. In particular, support of queries involving evaluations of set predicates is often required in handling complex obje...
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Logres is a new-generation database system integrating features from deductive and object-oriented databases [1, 2, 3, 4, 5]. The data model of Logres supports structural and semantic complexity through a rich collect...
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