VLDB

A comprehensive tutorial is presented on the subject of lockinq and recovery. The viewpoint taken is that of the application proqrammer (primarily). The material covered represents a synthesis of ideas from many sources; in particular, the lanquage UDL ...

Spatial Data Management is a technique for organizing and retrieving information by positioning it in a Graphical Data Space (GDS). This Graphical Data Space is viewed through a color raster scan display which enables users to traverse the GDS surface ...

If a data base query fails, i.e., if the required information is not available, contemporary data base systems report the fact that the query failed rather than the actual reason for the failure. We argue that the deeper reason for a failure may be ...

This article examines data base description problems from the point of view of logic programming, and presents an experimental deductive data base system implemented in PROLOG.

We first discuss the advantages of logic for describing data bases, in a ...

The system described in part in this paper is one of the ongoing research efforts to provide powerful automated tools for coping with data base error detection. Intended as a "filter" between the users and their DBMS, the Cooperative Overt Passive Error-...

It is shown that it is possible to automatically generate all valid answers to a query on a relational data base such that the user need not be aware of the relations used to form the answer, but can express queries simply in terms of attribute names.

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The role of null values in a relational data base is considered within the framework of multivalued dependencies. When a relation contains null values, a different treatment of data dependencies and different relational operations such as projection and ...

Recently Delobel and Parker have shown that Multivalued dependencies (MVDS) may be represented as Boolean switching functions, in much the same way as Functional dependencies (FDs) can be represented as Boolean implications. This permits all FD and MVD ...

Mutual dependencies have been shown to provide a necessary and sufficient condition for a relation to be decomposable into three of its projections. We generalize the notion of mutual dependency by extending it to any number of sets of attributes and ...

In this paper we describe some features of the decision support system which is currently being built on top of the distributed DBMS POREL. Based on a short description of the different interfaces of POREL we investigate the relationships between the ...

The problem of scientific documentation in developing countries is very important, as everybody knows. The aim of this paper is to present the implementation of the International Road Research data base in the National Laboratory of Civil Engineering, ...

The paper describes a problem, oriented representation for information flow systems ("information systems"), and an (existing) implementation which interprets the problem descriptions, and which thereby permits demonstration, testing, and modification ...

It is argued that the conceptual schema should contain an ontological subschema (i.e. a "reality" model). It is shown how one particular ontological meta-model can be interfaced to meta-models for the development of software requirement specifications. ...

We propose as an extension to the CODASYL Data Description Language a new external schema facility more powerful than that presently offered by CODASYL subschemas. We note that the present facility relies on records and sets that closely resemble those ...

This paper suggests that two levels should be considered when designing a conceptual schema: the 'understanding level' and the 'conceptual data base level'. The first level includes two realms of importance • the set of information requirements (IRQ) ...

A data base design aid, SYDADA, is introduced. Input to SYDADA is a requirements specification, expressed in a language called SYSDOC. A SYSDOC specification consists of two main parts: a conceptual data model and a transaction description. The ...

It has been recently shown that the technique of periodic updating of a key-sorted data base from a key-sorted "transaction file" may be considered to be used even in online data bases. In this paper, a backout mechanism is described which exploits the ...

A new file organization method, providing very high performance for a large class of associative queries. is abstractly defined. The organization may be viewed both as a development of the fully transposed file, and as a generalized trie. Its average ...

A special UNDO-log algorithm combining the advantages of update-in-place strategies with the shadow page concept is introduced. It is to support applications demanding high rates of updating transactions as well as fast UNDO-recovery. By doubling the ...

In this paper we have tried to give an idea of some of the VLDBs which are used for advancement of developing countries. There are not many VLDBs which fall in this category and are public knowledge. The number of VLDBs in developing countries is ...

Translation of large mechanized banks of data from one computer stored form to another represents a major investment. The translation is frequently necessitated by evolving hardware and software systems. Standardization of data structures across various ...

In order to have an effective logical database design tool, a designer should have facilities for specifying his data and application requirements at a high level. These specifications should be invariant with respect to a given realization, and should ...

This paper proposes that a DBMS of the kind typically used in a COBOL application environment should have facilities to implement automatically the monitoring of the integrity constraints specified at the conceptual level. In particular it is suggested ...

An analytical approach to the design of logical database structures is presented. Inputs to the model consist of data item types and volume, associations among items, security constraints, and item access frequencies required to satisfy known database ...

A new operator, the entity join, is proposed as an extension to the relational model. While similar to the traditional join, it is based on common entities rather than matching representations. The entity join avoids a number of problems arising from ...

A number of high-level data manipulation languages have been proposed for the relational model. This paper summarizes results of an analysis of languages and attempts to evaluate various criteria as to their capability of accounting for differences ...

In the former VLDB Conference we have presented a global model for the design of a complete information system (IS). This model constitutes an original attempt to integrate at the conceptual level, data, processes and dynamics in the design of IS. In ...

Among the different phases of the data base design process, the phase of modelling user's views has a particular relevance. This paper describes an interactive methodology for designing the views starting from the elementary sentences that specify the ...

The organization of an autonomous processor supporting database management functions is presented. The DataBase Concurrent Processor (DBCP) can be thought as a back-end data management machine of a general purpose host computer; it supports relational ...