A formal system for information retrieval from files

Abstract

A generalized file structure is provided by which the concepts of keyword, index, record, file, direcfory, file structure, directory decoding, and record retrieval are defined and from which some of the frequently used file structures such as inverted files, index-sequential files, and multilist files are derived.Two algorithms which retrieve records from the generalized file structure are presented.KEY WORDS AND PHRASESr attribule-volue pair, index, keyword, record, record address, K-pointer, K-Iisl, file, directory, generalized file structure, inverted file, index-sequential-file, multilist file, description, file search, directory search, serial processing of lists, prime keyword, parallel processing of lists CR CATEGORIES: 3.70, 3.73, 3.74The object is to develop a formal approacli to the characterization and classification of file structures with a view toward information retrieval. To this end, we first develop definitions. All the abstract concepts to be introduced stem from the real world and are so illustrated. The construction of a generalized file structure to embrace some of the known file organizations and a general algorithm for parallel processing of lists are believed to be new. File StructureDConsider two undefined terms: a set A of "attributes" and a set V of "values." A record J? is a subset of the Cartesian product A X V in which each attribute has one and only one value. Thus fl is a set of ordered pairs of the form: (an attribute, its value).

Selection of file organization using an analytic model

“…Senko, et al, [9] and Lurn, et al [6] have modeled and studied the indexed sequential access method in detail. Hsiao and Harary [3] introduced a formal model for list oriented file structures. Lefkovitz [5] and L. Martin [7] have also modeled list oriented file structures, and have developed a set of cost equations.…”

A Hybrid Access Method for Bibliographic Records

“…Hsiao and Harary propose an abstract model for file structure that encompasses those that are discussed most frequently. 1 Lefkovitz discusses these techniques in more detail and considers the advantages of each for implementation, while Dodd and Knuth describe the data structures needed in implementing such files. 2 -4 These works reveal the interrelation between a file's organization and its retrieval capability, but the determination of which routes of access to provide must be the task of those responsible for creating the file.…”

An interactive DSS tool for physical database design

“…Prior works have generally dealt with and developed design/optimization models for specific aspects of physical database design. These works include: index selection [1,14,17], file structuring and models of file organization [18,30], and record segmentation and structuring [15,17,23,24]. Some of these models are reviewed in [29].…”