Page 623 - Introduction to Business

CHAPTER 17 Management Information Systems 597

pute the sum of two numbers as expressed by the formula A B C, a fourth-
generation language statement would be
SUM THE NUMBERS B AND C 6

Databases
From a computer hardware perspective, a bit is the most elementary data element.
However, from a logical perspective, the most basic data element that can be
observed and manipulated is a character, which can be a number, a letter, or character The most basic data
another symbol. A field is a grouping of characters. For example, the grouping of element—a number, letter or other
symbol—that can be observed and
letters in a person’s name forms a field that could be called the name field, the
manipulated
grouping of numbers in a person’s social security number forms a field that could
field A grouping of characters
be called the SSN field, and the grouping of numbers in a person’s salary forms a
field that could be called the salary field. A record is a collection of related fields. record A collection of related fields
For example, if for two employees we have

Name field: John Smith Name field: Guadalupe Garcia
SSN field: 137-47-2239 SSN field: 932-11-4567
Salary field: $35,0000 Salary field: $50,000
then the collection of the first three fields would constitute the payroll record of the
first employee and the collection of the second three fields would constitute the
payroll record of the second employee. It is said that a record represents a set of
attributes, characteristics or qualities, that describe an entity, an object, person,
place, or event. Hence in the payroll record example, the entity is the employee and
the attributes are the name, social security number, and salary.
A file is a group of related records. Thus the collection of payroll records for all file A group of related records
employees in a business organization constitute the payroll file. Files are also called
tables. A database is a group of related files and represents the highest level in the database A group of related files that
represents the highest level in the data
hierarchy

Oracle Corporation is the largest
supplier of databases in the world.
Reprinted with permission of Oracle
Corporation.

Copyright 2010 Cengage Learning, Inc. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.