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What is database and explain characteristics of database ?

Data: A data is a piece of information or facts. A data can be in any form like numbers, texts, piece of paper, measurements and bytes. For example, Student name, age, class, roll no. image etc. A file, pdf and document can also be a data.

A database is an organized collection of data. It is the collection of schemas, tables, queries, reports, views, and other objects.

OR

Database is a collection of related data and data is a collection of facts and figures that can be processed to produce information.

Key features of DATABASE.
  • Database is always well ordered.
  • Database is interlinked.
  • It is stored only once.
  • Easy retrieval of information
  • Made up of fields, records and files
For example a phone book carrying thousand of numbers in it is the basic example of database. In phone book you can search any number without any problem because all the numbers are arranged in a systemic order.
Other Examples are: Electric Service Provider, Address Book and Bill Book Etc.

 Characteristics of database

 Self Describing nature
A database is of self describing nature; it always describes and narrates itself. It contains the description of the whole data structure, the constraints and the variables.
It makes it different from traditional file management system in which definition was not the part of application program. These definitions are used by the users and DBMS software when needed.

Represent Some Aspects of real world applications
A database represents some features of real world applications. Any change in the real world is reflected in the database. If we have some changes in our real applications like railway reservation system then it will be reflected in database too.
For example, let us take railway reservation system; we have in our mind some certain applications of maintaining records of attendance, waiting list, train arrival and departure time, certain day etc. related to each train.

Manages Information
A database always takes care of its information because information is always helpful for whatever work we do. It manages all the information that is required to us. By managing information using a database, we become more deliberated user of our data.

 Easy Operation implementation
All the operations like insert, delete, update, search etc. are carried out in a flexible and easy way. Database makes it very simple to implement these operations. A user with little knowledge can perform these operations. This characteristic of database makes it more powerful.

Multiple views of database
Basically, a view is a subset of the database. A view is defined and devoted for a particular user of the system. Different users of the system may have different views of the same system.
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