MOD

We address the problem of automatically adjusting the physical organization of a data base to optimize its performance as its access requirements change. We describe the principles of the automatic index selection facility of a prototype self-adaptive ...

The File Design Analyzer is a software package which evaluates well-known database storage structures and access methods in terms of secondary storage processing time and storage overhead required to service a set of user applications. It implements a ...

In several file systems, the data in a file is described by constructing lists of records. Each list contains exactly those records for which some property is true. The motivation for constructing and maintaining these lists is to facilitate the ...

Buffer pools are created and managed in data base systems in order to reduce the total amount of accesses to the I/O devices. The use of the buffer pool in a virtual storage system may cause an increase in the page fault rate. We examine this phenomenon ...

Several techniques have been combined to provide for data base recovery at CMIC. The CMIC environment is presented first in order to identify the constraints which data base recovery must satisfy.A technique is described for updating mass-storage ...

The representation of a collection of data in terms of its differences from some pre-established point of reference is a basic compaction technique which finds wide applicability. This paper describes a differential database representation which is ...

In a multi-task computer system many different types of situations may occur in which productive computation may be brought to a standstill. One of these is deadlock or "deadly embrace". Some of the earliest investigation into this problem was ...

A multi-user data base system must permit users to selectively share data, while retaining the ability to restrict data access. There must be a mechanism to provide protection and security, permitting information to be accessed only by properly ...

Current research in the area of database design has been directed towards the development of structured or automated database design techniques. The first phase of the database design process, information requirements specification and analysis, is ...

The conventional concept of file is reexamined, and found to be unsatisfactory, both as a linguistic concept in a programming language and as a tool for data processing. A new file concept is proposed which unlike the conventional file attempts to ...

Efficiency is of paramount importance in very large databases. A principal technique for increasing efficiency is to define the user's view of the data independently of the storage structure so that the storage structure can be varied at will to improve ...

The concept of normalisation and the definition of third normal form occupy a central place in the relational model of database. Normalisation has been described as an analytic process in which an initially unconstrained collection of relations is ...

This paper describes an architecture for a set of database extensions to the existing high-level languages. The scheme described forms an architecture in the sense that it is not based on any particular language: its constructs and functions, or some ...

This paper presents the main ideas behind the language LSL. The purpose of LSL is to provide a compromise between different data base approaches and attitudes. The hierarchical, network and relational models of data can coexist within the LSL ...

This paper presents an end-user's language which tries to solve the problem of an easy navigation through a DBTG-like data base structure. A request is expressed in a nonprocedural and hierarchically structured fashion. The dialogue is split into two ...

An Access Path Producing LanguagE (APPLE) has been developed which permits users to formulate completely non-procedural queries expressed solely in terms of attribute names. The responsibility for programming or specifying the access path by which a ...