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The need for databases is as follows: Amit Sen Amit Sen Microsoft Access, Oracle, MySQL, etc. are some of commonly used RDBMS.
Richa Tondon Richa Tondon
Reduction of data redundancy: It refers to unnecessary Deepak Patel Deepak Patel DBMS vs RDBMS
duplication of data. A centralised database helps avoid this Nitish Reddy Nitish Reddy
Anil Gurang Anil Gurang Table Table
by storing only one version of the data. Amit Sen
Richa Tondon Table
xml Table Table
Data sharing: It allows multiple users to access and xml
work on the same data simultaneously, facilitating xml Table The Relational Model was proposed in
xml 1970 by E.F. Codd of IBM.
real-time collaboration. xml
DBMS RDBMS
Data security: It ensures data safety through security systems, user
roles and permissions, allowing only authorised users to access and COMPONENTS OF RELATIONAL DATABASE

modify the data.
The key components of a relational database are as follows:
Student Table

Data integrity: Data integrity ensures that data is accurate, Fields
consistent and reliable. Databases use constraints to prevent errors, Student_ID First_Name Last_Name Date of Birth Email Course_ID
such as disallowing negative quantities or verifying that a supplier 1 Aarav Sharma 15-Mar-2012 aarav.sharma@gmail.com C101
exists before processing an order. 2 Priya Patel 20-May-2012 priya.patel@gmail.com C102
Table 3 Rahul Verma 10-Mar-2012 rahul.verma@gmail.com C103 Records

4 Sneha Iyer 25-Nov-2011 sneha.iyer@gmail.com C101
Data backup: Data backup in databases means making a copy of the 5 Dev Kapoor 12-Jul-2012 dev.kapoor@gmail.com C102
database files so that you can restore your data if it gets lost, damaged
or corrupted. It is a safety measure to protect important information. The different components of a relational database are as follows:

Tables: A table is a collection of related records arranged in rows and columns. Each column
represents a specific type of information (attribute) and each row represents a record (tuple)
DATABASE MANAGEMENT SYSTEM (DBMS) containing related data.

A Database Management System (DBMS) is a software that allows users to control the creation, Fields: A field represents one related part of a table. It contains the same kind of data in a
maintenance and use of a database. It performs the tasks of maintaining databases so that the table. For example, Student_ID, First_Name, Last_Name, Date of Birth, Email and Course_ID

information is readily available. It helps to manage the data of different fields like banks, offices, are fields in the table.
railways, airlines, etc. DBMS allows users to store, manage and organise all the data in a way that Records: A record is a collection of related data stored in different fields, treated as a single
makes it easy to find and use whenever they need it. unit. It represents the data which is entered in a set of different fields which are related to a
particular item. For example, 1, Aarav, Sharma, 15-Mar-2012, aarav.sharma@gmail.com and
C101 is one of the records of the table.
RELATIONAL DATABASE MANAGEMENT SYSTEM (RDBMS)
KEYS IN DATABASE
A relational database is a type of database that stores data in the form of tables. These tables are A key is a column or set of columns that identifies records in a table. It is also called a key field and
structured with rows and columns and they can be related to each other through common fields can link data between tables. The most common types of keys in SQL are the primary key and the
(keys) to enable the retrieval of related information. The software package that is used to handle foreign key.
relational databases is known as the Relational Database Management System (RDBMS).

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MySQL: My First Database