What is Database Management System?
A database-management system (DBMS)
is a collection of interrelated data and a set of programs to access those
data. This is a collection of related data with an implicit meaning and hence
is a database. The collection of data, usually referred to as the database, contains information relevant
to an enterprise. The primary goal of a DBMS is to provide a way to store and
retrieve database information that is both convenient
and efficient. By data, we mean known facts that can be
recorded and that have implicit meaning.
The management system is important because without the existence of some
kind of rules and regulations it is not possible to maintain the database. We
have to select the particular attributes which should be included in a
particular table; the common attributes to create relationship between two
tables; if a new record has to be inserted or deleted then which tables should
have to be handled etc. These issues must be resolved by having some kind of
rules to follow in order to maintain the integrity of the database.
Database systems are designed to manage large bodies of information.
Management of data involves both defining structures for storage of information
and providing mechanisms for the manipulation of information. In addition, the
database system must ensure the safety of the information stored, despite
system crashes or attempts at unauthorized access. If data are to be shared
among several users, the system must avoid possible anomalous results.
Because
information is so important in most organizations, computer scientists have
developed a large body of concepts and
techniques for managing data. These concepts and technique form the focus of
this book. This chapter briefly introduces the principles of database systems.
