d. Other Features of a Database. The database, however, is more than just a
collection of files, it is a collection of data elements that have various relationships to
one another. Think of the files in a database like the books in a library. In a library,
there are many books (files). Some books have footnotes. These footnotes establish
relationships between data elements in one book (file) and data elements in other books
(files). The footnotes establish relationships between different books that go beyond
book (file) boundaries. Similarly, a database, through its cross- referencing, establishes
relationships between different files.
e. Data Base Management System. The software that enables a data base to
be defined, created, retrieved, and modified by a variety of users as needed is called a
database management system (DBMS).
database management system: a set of programs that provides a method of
storing, manipulating, retrieving, and displaying information in the database.
These methods minimize duplication, permit changes easily, and feature- a
(1) Consists of versatile programs. The DBMS consists of a series of
versatile programs that can sort information in many different ways. Information,
entered in the form of records, contains all the necessary information about a specific
item in the database. The programs in the DBMS can selectively sort records or
generate lists. The main function of the DBMS is to create, maintain, and process the
database independently of the application programs that need to use it. The
programmer specifies the data elements that are needed for the program and the form
in which they should appear. The DBMS finds those elements, arranges them as
desired, and presents them to the program.
(2) A set of tools for accessing information. The data base management
system is a set of tools that provides users with access to data in a database. Data
base management systems vary as to efficiency and speed with which information can
be retrieved from the database. The quality of a DBMS will depend on the skill of the
data base designer and user in structuring the data base so that data can be accessed
with a minimum of steps.
a. An Electronic Financial Worksheet. In 1980-81, the spreadsheet, an
electronic version of the financial worksheet, provided yet another important tool for
management. Anyone who has tried to plan a budget knows how time-consuming it can
be to enter columns and rows of figures accurately and efficiently. Too much time is
spent unproductively recalculating totals that have to be changed every time one or
another number in the worksheet is changed.