MANAGING COMPUTER FILE
COMPUTER FILE: Computer file is a resource for storing information which is available to a computer program and is usually based on some kind of durable storage.
RECORD: A record is a collection of elements typically in fixed number and sequence and indexed by serial numbers or identity numbers.
FIELD: This is a document that provides direction or instruction to a given set of data.
DATA ITEM: It is a file that is contained within a catalog directory or folder.
TYPES OF DATA ITEM
i) Numeric: Numeric refers to numbers only.
ii) Alphabetic: Alphabetic is data that are in alphabets only.
iii) Alphanumeric: Alphanumeric is data stored with combination of number and alphabet.
FILE STRUCTURE: It addresses them to application in data management which reflected in the terminology used to describe the basic concepts.
TYPES OF FILE ORGANISATION
SEQUENTIAL: It means all records are stored in a sequential form i.e. it is arranged in the ascending or descending order of a key field.
RANDOM: Record is stored in Direct Access Storage Device (DASD) such as magnetic disk (hard disks). It is useful for immediate access to large amount of information. They are often used in accessing large data bases.
INDEX: It combines the positive features of both the sequential and direct access file organization.
SERIAL: All record is stored in serial form.
METHOD OF ACCESSING FILES
i) Master file
ii) Transaction file
iii) Reference file
CRITERIA FOR CLASSIFYING FILES
i) Nature of content (program and data)
ii) Organization method
iii) Storage medium