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Relational Database: It is a type of database that stores
data in several tables and links those tables together
through keys that allows efficient data retrieval and
reduced redundancy. Commonly used relational database
systems are LibreOffice Base, Microsoft Access, etc.
Clickipedia Relational Databases
The relational database was proposed by Edgar F. Codd. He gave a set of thirteen rules
(Codd’s rules) to define a Relational Database Management System.
ADVANTAGES OF A DATABASE SYSTEM
A database system has many advantages. Some of the important advantages are:
It minimises the redundancy of data by organising data in a structured manner. This ensures
that data is not unnecessarily repeated across tables.
It saves the storage space.
All the users are provided with some access rights or privileges and permissions.
The files can be easily updated whenever changes are being made.
TERMS RELATED TO A DATABASE
Data is stored in the table of a database, as shown in below diagram.
FIELDS
Reg No. Name Father’s Name Date of Birth Class
187/11 Aashi Kant Mr. P.S. Kant 15/08/2007 VIII
RECORDS 156/12 Nazia Sharma Mr. R.K. Sharma 22/10/2008 IX
Mr. V.S. Patel
Rajesh Patel
194/11
16/04/2008
IX
123/12 Niraj Sagar Mr. A.K. Sagar 18/06/2007 VIII
The commonly used terms of the relational database are:
Table: It is a group of related data organised in columns and rows in a database. The columns
contain a number of headings such as Reg No., Name, Father's Name, Date of Birth, Class, etc.
These are known as fields. A set of values for the fields is called a Record. Each row in the
table represents one record.
Primary Key: It is a unique field by which the records are uniquely identified in a table. A
table can have only one primary key. It ensures that no two records have the same value for
this field. For example, in a student’s record the ‘Reg No.’ can be called a primary key.
Query: A query is the most powerful feature of database. It allows you to retrieve information
from a table based on some criteria or condition. By creating and running a query, you can
search, filter, and extract data from the database efficiently.
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