- There are numerous types of files used for storing data needed for processing, reference or back up. The main common types of processing files include
- Master files,
- Backup, report and
- Sort file.
- Master file
- A master file is the main that contains relatively permanent records about particular items or entries. For example a customer file will contain details of a customer such as customer ID, name and contact address.
- Transaction (movement) file
A transaction file is used to hold data during transaction processing. The file is later used to update the master file and audit daily, weekly or monthly transactions. For example in a busy supermarket, daily sales are recorded on a transaction file and later used to update the stock file. The file is also used by the management to check on the daily or periodic transactions.
A reference file is mainly used for reference or look-up purposes. Look-up information is that information that is stored in a separate file but is required during processing. For example, in a point of sale terminal, the item code entered either manually or using a barcode reader looks up the item description and price from a reference file stored on a storage device.
A backup files is used to hold copies (backups) of data or information from the computers fixed storage (hard disk). Since a file held on the hard disk may be corrupted, lost or changed accidentally, it is necessary to keep copies of the recently updated files. Incase of the hard disk failure, a backup file can be used to reconstruct the original file.
Used to store relatively permanent records extracted from the master file or generated after processing. For example you may obtain a stock levels report generated from an inventory system while a copy of the report will be stored in the report file.
It stores data which is arranged in a particular order.
- Used mainly where data is to be processed sequentially. In sequential processing, data or records are first sorted and held on a magnetic tape before updating the master file.