Make a clear difference between:-
- Logical file and physical file – Viewed in terms of what data items it contain and details of what processing operations may be performed on the data items. Physical files is one that is viewed in terms of how data is stored on a storage media and hoe the processing operations are made possible.
- Master file and back-up file – Master file is the main file that contains relatively permanent records about particular items or entries. Back-up file is used to hold copies of data or information from the fixed storage (hard disk)
- Random and indexed sequential file organization methods. Random – Also direct file organization records are stored randomly but accessed directly on a storage medium. Indexed sequential records are stored and accessed in a particular order using an index used to enable the computer to locate individual records on storage media.