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A database management system (DBMS) is an important type of programming system, used
today on the biggest and the smallest computers.
[1]
As for other major forms of system software,
such as compilers and operating systems, a well-understood set of principles for database
management systems has developed over the years, and these concepts are useful both for
understanding how to use these systems effectively and for designing and implementing DBMS's.
DBMS is a collection of programs that enables you to store, modify, and extract information
from a database. There are many different types of DBMS's, ranging from small systems that run
on personal computers to huge systems that run on mainframes. The following are the location of
database between application programs and end-users.
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There are two qualities that distinguish database management systems from other sorts of
programming systems.
1) The ability to manage persistent data, and
2) The ability to access large amounts of data efficiently.
Point 1) merely states that there is a database which exists permanently; the contents of this
database is the data that a DBMS accesses and manages. Point 2) distinguishes a DBMS from a
file system, which also manages persistent data. A DBMS's capabilities are needed most when
the amount of data is very large, because for small amounts of data, simple access techniques,
such as linear scans of the data, are usually adequate.
[2]
While we regard the above two properties of a DBMS as fundamental, there are a number
of other capabilities that are almost universally found in commercial DBMS's. These are:
Support for at least one data model, or mathematical abstraction through which the user can
view the data.
Application
program
End-user
DBMS
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