Sunday, 18 September 2011
COMPUTER FILE-BASED PROCESSING SYSTEM
Before to understand the characteristics of a pure database system, it is necessary to know about the computer file-based processing system, which was used in the past (before the database system). In computer file-based processing system, the data is usually kept in computer files on magnetic disk or tape. In a typical computer file-based processing system, each department has its own set of application programs and data files. Data is stored and managed in data files through application programs. In computer file-based processing system, each department (or user) defines and implements the data files needed for a specific application. Each application program is developed with its own set of data files to meet the needs of a particular department.
For example, the admission office of a college may have an application program for maintaining records of candidates for admission in the college. The admission office forwards information about enrolled students to the head of the department (or dean or registrar). If the information of students/candidates comes in the form of printed reports, then they must be re-entered into the computer. Similarly, concerning courses offered, schedules, and so on. The dean's office may have its own students file, course file, as well as faculty file. In each case, all departments or offices have their own data files. The departments/offices of the university shares the information by copying data files on disk or by obtaining printout by the permission of the owner.