Essentials of computer data files
Owen Hanson · Medical Entomology and Zoology · 1985
CONTENTS Preface Introduction 1 Business applications of computers: a brief review Introduction Information storage Types of data file The concept of data records Data fields Organization of information files Accessing data files Data file storage File processing functions Other terms used Revision questions 2 Storage devices Magnetic tape Direct-access devices Device performance and uses Data recording Alternatives to disk Conclusion Revision questions 3 Choice of file organization Reference facility Activity Volatility Size Growth Security/backup Design review Revision questions 4 The influence of record format on design Introduction Record length Fixed or variable format Record layout Optimum blocking factor Conclusion Revision questions 5 Sequential file design Introduction Sequential files on magnetic tapes Sequential files on direct-access devices Sequential files - tape or disk? Revision questions 6 Direct file design Introduction Addressing concepts Minimizing the number of synonyms Conclusion Revision questions 7 Indexed-sequential file design Introduction Optimizing IS files Processing indexed-sequential files Developments of indexed-sequential files-VSAM and independent software packages Conclusion Revision questions 8 Inverted files and information retrieval Applications Possible file organizations Library uses Conclusion Revision questions 9 Special-purpose files User-designed files Proprietary software Revision questions 10 File design for on-line systems Introduction Availability Response time The effect of file organization and structure The choice of file hardware Conclusion Revision questions 11 Introduction to database systems Introduction The database approach Logical and physical databases DBMS selection File sructures in database systems Revision questions 12 Security of data files Introduction Avoiding read-write errors Restarting a run Repeating a run Recovering from disaster Security in on-line and database systems Conclusion Revision questions 13 Case studies in file design Introduction 1 Tape blocking 2 Indexed sequential or sequential? 3 Use of checkpoints in a specific case 4 Direct or indexed sequential? Conclusion Revision questions 14 Review of the literature General Record format and handling Sequential files Direct files Indexed-sequential files Choice between file organizations Database systems On-line systems Security Use and performance of input-output devices References Appendix: Useful prime numbers Index