This paper discusses function materialization for features of objects in object-oriented databases, and identifies its role in design databases. Drawbacks with the present approaches are discussed and a new approach t...
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An object-oriented database provides persistent storage for a large number of objects. These objects may be very small, and the access patterns are likely to be not as uniform as the mostly sequential reads and writes...
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In this paper a class-based logic language for object-oriented databases which is called CLOG is described. CLOG is based on many sorted horn clauses with concept of classes, objects, object identity, multiple class m...
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This paper describes practical design and implementation experiences gained when creating Group Support Systems (GSS) in a networked personal computer environment. Examples of GSS based on the shared context model and...
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This paper describes practical design and implementation experiences gained when creating Group Support Systems (GSS) in a networked personal computer environment. Examples of GSS based on the shared context model and implemented using C, C++, and Actor languages are presented. Graphical user interfaces and multitasking extend traditional methods for supporting group work. An object-oriented communication system is introduced comprised of objects that provide support for all inter- and intraprocessor communications between the GSS applications. Multiple levels of data service are provided to maintain shared data, coordinate user views, and transmit cursor positions in a convenient and efficient manner. The applications presented not only demonstrate the viability of implementing GSS on personal computer-based systems, but also show the ability to develop complex applications in different programming environments that make use of common routines. The unique properties of the object-oriented paradigm greatly facilitate the creation and use of Group Support Systems.
Flora is a functional-style language For object and relational algebra. It has been designed for efficient support of advanced database languages combining rules and objects using compilation and optimization. Flora i...
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Flora is a functional-style language For object and relational algebra. It has been designed for efficient support of advanced database languages combining rules and objects using compilation and optimization. Flora is a strongly typed language based on an OO data model and incorporating support For collection-oriented computational capabilities. In this paper, we describe the design and architecture of the Flora optimizer which is rule-based, yet doing cost-based optimization. The optimizer uniformly captures logical, semantic and implementation knowledge regarding the execution system and the applications by means of assertions. This framework eases extensibility and enables efficient query rewriting.
This paper presents an approach to implementing production rules for object-oriented databases (OODBs). The approach builds upon earlier work on production rule algorithms for relational databases, and exploits fundam...
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This paper presents an approach to implementing production rules for object-oriented databases (OODBs). The approach builds upon earlier work on production rule algorithms for relational databases, and exploits fundamental differences in the structuring mechanisms employed by OODBs. An implementation is described whereby the production rules are mapped onto event-condition action rules for execution, It is shown how the resulting implementation has minimal space overheads, and a time performance close to that of the widely used TREAT algorithm which uses significantly more space.
The generation of execution plans for object-oriented database queries is a new and challenging area of study, Unlike the relational algebra, a common set of object algebra operators has not been defined, Similarly, a...
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The generation of execution plans for object-oriented database queries is a new and challenging area of study, Unlike the relational algebra, a common set of object algebra operators has not been defined, Similarly, a standardized object manager interface analogous to storage manager interfaces of relational subsystems does not exist. We define the interface to an object manager whose operations are the executable elements of query execution plans, Parameters to the object manager interface are streams of tuples of object identifiers. The object manager can apply methods and simple predicates to the objects identified in a tuple. Two algorithms for generating such execution plans for queries expressed in an object algebra are presented. The first algorithm runs quickly but may produce inefficient plans, The second algorithm enumerates all possible execution plans and presents them in an efficient, compact representation.
In this paper we present an indexing technique providing support for queries involving complex, nested objects and inheritance hierarchies. This technique is compared with two techniques obtained from more traditional...
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In this paper we present an indexing technique providing support for queries involving complex, nested objects and inheritance hierarchies. This technique is compared with two techniques obtained from more traditional organizations, The three techniques are evaluated using an analytical cost model. The discussion will be cast in the framework of object-oriented databases, However, results are applicable to data management systems characterized by features such as complex objects and inheritance hierarchies.
This paper describes a model for developing applications of active object-oriented databases based on three orthogonal concepts;methods, guards and actions and a tool which implements these ideas called MGA. MGA objec...
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This paper describes a model for developing applications of active object-oriented databases based on three orthogonal concepts;methods, guards and actions and a tool which implements these ideas called MGA. MGA objects are active;they have guards which constrain the object's state, actions which maintain database integrity when the object's state changes, and methods through which the object provides other services. These active components are implemented as (collections of) rules and rules are in turn modelled as objects.
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