The CODASYL Approach to Data Base Management. T. William Olle. Chichester, England: Wiley-Interscience; 1978: 287p. Price: $21.50
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The information professional should by now have become familiar with the use of computerized data base systems to provide retrieval of bibliographic references to documents. However, the overall structure and operational technology of systems that can retrieve data or facts of all types are often left unmentioned in the information science literature. This book is another addition to a growing list of books that present material on the rapidly advancing area of data base management systems (dbms). It provides us with a very good understanding of one specific approach to data base management. The book is intended as a tutorial and a text on the topic, and the target audience is students and information system practitioners. The overall organization, style, and format are quite good for this objective. However, it is imperative that the reader have some understanding of the basic principles of a computerized data processing system, with an emphasis on data structures. Moreover, a knowledge of a programming language, preferably COBOL, is highly recommended. Chapter 1 presents a delightful, but all too brief, historical perspective of the origins of data base systems and the work of the Conference on Data Systems and Languages (CODASYL) in this area. More could have been said about the earlier work of CODASY L, including the development of the COBOL programming language. Chapter 2 presents a general discussion of a dbms, with definitions of several terms. The book fails as an introductory text because a thorough understanding of these concepts, the different approaches to modeling a data base, and the nature of the problems to be addressed cannot be properly mastered with such a short coverage of the topic. However, the book is much more than adequate as a reference for a reader with some exposure t o this area. Chapter 3 introduces the basic logical structure of data as viewed in the CODASYL approach. The use of terms (such as “set” used to indicate a pair of record types and a relationship between the two records) which have other meanings demonstrates the problems with terminology rampant in this discipline. Chapters 4 and 5 present methods of mapping records and sets to storage, while Chapter 6 discusses sorting records and the use of a search key for retrieval. These last three chapters also begin to define and illustrate the syntax and use of specific commands that a dbms would employ. Chapters 7-10 are concerned with data manipulation. This includes insertion, deletion, and updating of records, as well as retrieval of records. The emphasis is o n descripA unique new text on the scientific handling of information.