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In this a view named "STUDENT_1" is created with a condition for "Name" column as NOT NULL, if
we now try to insert a new row with null value in the ‘Name’ column then it will give an error because

"Name" does not allow NULL. The clause WITH CHECK OPTION prevents entering any value that do
not match with the view conditions, mentioned at the time of its declaration.
A view can be deleted entirely(including its structure) using DROP VIEW command. Syntax is as

follows:
Hands On
DROP VIEW view_name;

For example: Create Authors (AuthorID, Name, Country)
DROP VIEW PRODUCT_SALES; and Books (BookID, AuthorID, Title,
Year) tables. Then, create a view AuthorBooks
The above command deletes
that shows author names and the titles of the
the entire structure of the view
books they’ve written. Finally, write a query to
Student_1.
retrieve data from the AuthorBooks view.
Views can be used for security
purposes. View doesn’t contain
data of its own it only holds the data temporarily. Commands like DROP VIEW and ALTER VIEW do
not affect underlying data, commands like INSERT/UPDATE/DELETE in a view do affect base tables.
So effective use of views is in the hands of the programmer.

INDEX

An index is a structure that is used to improve the performance of database activity. Index helps in

quick data retrieval and it acts like an index page of a book that helps in quick access to the required
page of the book. Similarly index in MySQL saves time for scanning of database entirely and reaches
to the required piece of data quickly. It makes the process of search faster and efficient. It helps the
pointer to reach the desired record rather than sequentially going through each record one by one.
It is a mechanism which help to quickly retrieve a record from a table or a view. A database table can
have one or more indexes associated with it.

CONTENTS

This page numbering
01 Introduction to DBMS 7 will help ease in
Understanding Database and DBMS What is a Relational Database?
Keys Understanding SQL moving quickly to the
Different Types of Commands in SQL Modern DBMS
02 Introduction to MySQL 14 desired chapter/topic
Installing MySQL Data Types in MySQL
Creating a Database Creating a Table
Modifying a Table Deleting a Table
03 Handling Records in MySQL 24
Inserting Records in a Table Retrieving Records from a Table
Updating Records in a Table Deleting Records from a Table
Using DISTINCT Clause Using Operators
MySQL Comments
Test Sheet-1 34
04 More on MySQL 36
Aliasing Performing Calculations in Queries
Using Group By Using Order By
Function
05 Advanced Features of MySQL 46
Subqueries Joins
Views Index
Test Sheet-2 64
Project Work 66
Explore More (Latest Trends) 68
Uncover Artificial Intelligence & Robotics 73
OGO Cyber Sample Questions 77
Glossary 80
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