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• All the users are provided with some access rights, privileges, and permissions.
• The files can be easily updated whenever any changes are made.
i + TYPES OF DATABASES
There are mainly two types of databases:
• Flat File Database: It is a type of database that contains records having a small
number of fields without any structured relationship between them. The most
popular example of a flat file database is Excel 2016. Excel 2016
• Relational Database: It is a type of database that stores
data in several tables and links those tables together to
get a common piece of information. Commonly used
relational database systems are Microsoft Access, Microsoft SQL Server, ORACLE, etc.
Info Byte
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.
i + TERMS RELATED TO A DATABASE
Data is stored in the table of a database as shown in the diagram given below.
FIELDS
Reg No. Name Father’s Name Date of Birth Class
187/11 Krishna Kant Mr. K.S. Kant 15/08/2007 VIII
RECORDS 156/12 Rishi Sharma Mr. N.K. Sharma 22/10/2008 IX
194/11
Suraj Patel
16/04/2008
IX
Mr. G.S. Patel
123/12 Priyansh Sagar Mr. P.K. Sagar 18/06/2007 VIII
The commonly used terms in a 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. A record is
one row of the table.
• 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. For example, in a student’s record, the ‘Reg No.’ can be
called a primary key.
• Query: A query is the most powerful object in a database. It helps you retrieve information
from a table based on some criteria or conditions. You can find, and retrieve data from the
database just by creating and running the query.
• Report: The final result of the manipulated data that comes from tables or queries in a DBMS
is known as a report. A report is a database object that is specially designed to display or print
the data in a formatted way.
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Database and DBMS—An Introduction

