CONCEPT OF COMPUTER FILES - DEFINITION OF TERMS (COMPUTER FILE, RECORD, FIELD, AND DATA ITEMS)

 

CONCEPT OF COMPUTER FILES 

DEFINITION OF TERMS (COMPUTER FILE, RECORD, FIELD, AND DATA ITEMS)

DEFINITION OF COMPUTER FILE

1. A computer file is defined as the smallest meaningful unit of data representation within a computer.

2. A computer file is a block of arbitrary information, or resource for storing information, which is available to a computer program and usually on some kind of durable storage.

FILE FUNCTIONS

Files are used to do one or more of the following functions:
a. They provide machine-executable code
b. They store application programs or operating system configuration
c. They store data used by the users such as Microsoft Word files.

COMPUTER FILE TERMS

1. Record: A record is a collection of related fields.
2. Field: Field is a single piece of information about an object. A field is also defined as a space that holds specific parts of data from a set or a record. Examples of fields are NAME, ADDRESS, QUANTITY, AGE, etc.
3. Data element: A data element is the logical definition of a field
4. Data item: Data item is the actual data stored in the field

TYPES OF DATA ITEMS

Each data element consists of only a single item. These items will have one of the three basic types: numeric, alphabetic and alpha-numeric.
1. Numeric data: Data consisting of digits and not letters of the alphabet or special characters. e.g 134, 400
2. Alphabetic data: Data consisting of letters and not digits or special characters. E.g JOHN, MARTINS
3. Alpha-Numeric data: Data consisting of digits, alphabets as well as special characters. e.g AG123, REG34200

FILE STRUCTURE DIAGRAM

CLASS ACTIVITIES

1. What is a computer file?

2. Differentiate between field and data item

3. Differentiate between alphanumeric and alphabetic data with four (4) examples each.