Traditional file design
William S. Davis · 2019
A file is a repository for a set of related data records, a program, a document, a spreadsheet, an image, an object, or some other logical entity. This chapter focuses on design options for data files. A file can hold data, a program, a document, a spreadsheet, an image, an object, or virtually any imaginable logical entity. The data in a file are typically structured using the standard field/record/file data hierarchy. A file is a set of related records. A master file holds permanent data that are managed or maintained over time. A transaction file holds data that describe current transactions. When a data file is first created, its name and physical secondary storage location are noted in a directory maintained by the operating system. Logically, the data in a file are read and written one record at a time. On a physical sequential file, records are read and written in physical storage order.