Why Database Design is Important? (or) Why do we need Database Systems?
https://www.computersprofessor.com/2016/06/why-database-design-is-important-or-why.html
Database design refers to the
activities that focus on the design of Database Structure that will be used to
store, manage end user’s data. Thus, a Database that meets all user
requirements does not just happen; its structure must be designed carefully,
which is a crucial step of database designing.
The database design therefore
requires the designer to identify precisely the Database’s expected use., by
designing a transnational Database emphasizes accurate and consistent data and
operational speed. More over, designing
a Database to be used in a Centralized approach for a distructured, multi-user
system is different from a single user environment. Thus, a well designed
Database facilitates Data Management and generates accurate and valuable
information.
Database Organization:
Earlier people used to maintain file
systems method for organizing and managing data over manual systems. The
problem with file system approach is, even for smallest data retrieval task, it
requires extensive programming. The need to write programs to produce even
simplest reports makes adhoc Queries impossible. Also, making changes in an
existing system (Structure also) can be difficult in a file system environment.
The Problem related to the need for
extensive programming is that, as the number of files in the system expands,
system Administration becomes more difficult. Another fault of a file system
database is that , security features are difficult to program and are
therefore, omitted in a file system environment.
The limitations of File system Data
Management , thus are,
Requires extensive programming.
Can not perform adhoc queries.
System Administration can be complex
and difficult.
Difficult to make changes to the
existing structures.
Security features are likely to be
inadequate etc.
Those limitations, in turn, lead to
problems of structural and data dependency. The File system exhibits structural
dependence, which means access to a file is, dependent on its structure itself.
Therefore, Data Redundancy, Data Inconsistency and Data Anomalies (Update
Anomaly, Insertion Anomaly, Delete anomaly etc) are major problems with File
Oriented database System Approach.
An efficient data management,
typically requires the use of Computer database, is a shared and integrated
Computer structure that stores collection of,
Meta data (Data about data)
Which is a collection of programs that
manages the Database Structure and controls access to the data stored in the
database.
A DBMS can thus support many
different types of databases. They are classified according to the number of
users, database location, expected type and extent of use.
A single user Database (DB) supports
and runs on a desktop, where as, a multi-user database supports multiple users
and relatively when small number of users within an organization. Then it is
called Workgroup DB. If it supports many users across many departments, then it
is called Enterprise DB.
A DB that support data located at a
single site is called Centralized DB. A DB that supports Data distributed
across several different sites, called Distributed DB. A DB that is designed
primarily to support Company’s day to day operations is called Operational DB
or Transactional DB or Production DB.
A Data warehouse focuses on storing
data used to generate information required to make Tactical or Strategic
decisions. Thus, DBMS Provides some of the advantages over File system are,
Improved Data Access
Improved Decision Making
DBMS is used to manage organizations
data, enables users to create DB including logical structure and constraints, manipulate the data, executes queries, generate reports etc. Besides users,
DBA works with the DB through an interface to administration, monitor, manage
and take backup and recovery management for the growing DB.
