DATA: THE NEW CORPORATE RESOURCE - Fundamentals of Database Management Systems - page 15

progressively became faster and cheaper on a price/performance basis. All these
changes had the effect of permitting the use of higher-level programming languages
that were easier for a larger number of personnel to use, allowing at least some of
the emphasis to shift elsewhere. Well, nature hates a vacuum, and at the same time
that all of this was happening, companies started becoming aware of the value of
thinking of data as a corporate resource and using it as a competitive weapon.
The result was the development of database management systems (DBMS)
software and the creation of the ''database environment.'' Supported by ever-
improved hardware and specialized database personnel, the database environment
is designed largely to correct all the problems of the non-database environment.
It encourages data sharing and the control of data redundancy with important
improvements in data accuracy. It permits storage of vast volumes of data with
acceptable access and response times for database queries. And it provides the tools
to control data security, data privacy, and backup and recovery.
This topic is a straightforward introduction to the fundamentals of database
in the current information systems environment. It is designed to teach you the
important concepts of the database approach and also to teach you specific skills, such
as how to design relational databases, how to improve database performance, and
how to retrieve data from relational databases using the SQL language. In addition,
as you proceed through the topic you will explore such topics as entity-relationship
diagrams, object-oriented database, database administration, distributed database,
data warehousing, Internet database issues, and others.
We start with the basics of database and take a step-by-step approach to
exploring all the various components of the database environment. Each chapter
progressively adds more to an understanding of both the technical and managerial
aspects of the field. Database is avery powerful concept. Overall it provides ingenious
solutions to a set of very difficult problems. As a result, it tends to be a multifaceted
and complex subject that can appear difficult when one attempts to swallow it in
one gulp. But database is approachable and understandable if we proceed carefully,
cautiously, and progressively step by step. And this is an understanding that no one
involved in information systems can afford to be without.
SUMMARY
Recognition of the commercial importance of data, of storing it, and of retrieving
it can be traced back to ancient times. As trade routes lengthened and cities grew
larger, data became increasingly important. Eventually, the importance of data led
to the development of electromechanical calculating devices and then to modern
electronic computers, complete with magnetic and optical disk-based data storage
media.
While the use of data has given many companies a competitive advantage in
their industries, the storage and retrieval of today's vast amounts of data holds many
challenges. These include speedy retrieval of data when many people try to access
the data at the same time, maintaining the accuracy of the data, the issue of data
security, and the ability to recover the data if it is lost.
The recognition that data is a critical corporate resource and that managing data
is a complex task has led to the development and continuing refinement of specialized
software known as database management systems, the subject of this topic.