This document discusses an introduction to structured query language (SQL) presented by Dr. C.V. Suresh Babu. The presentation covers SQL queries including SELECT, INSERT, UPDATE, and DELETE queries. Examples are provided for how to query, create, add, edit, and delete records from database tables. The document concludes with a quiz on SQL concepts.

1. Department of Information Technology 1Data base Technologies (ITB4201)
Introduction to
Structured Query Language (SQL) Part 2
Dr. C.V. Suresh Babu
Professor
Department of IT
Hindustan Institute of Science & Technology

2. Department of Information Technology 2Data base Technologies (ITB4201)
Action Plan
• SQL Introduction
• Simple Queries in SQL
• Quiz

3. Department of Information Technology 3Data base Technologies (ITB4201)
Database queries
• SELECT queries are used to extract information from a
database:
Example:
SELECT first_name, last_name
FROM president
WHERE state = ‘NY’;

4. Department of Information Technology 4Data base Technologies (ITB4201)
More database queries
• More examples
SELECT first_name, last_name
FROM president
WHERE birth_date like ’19%’;
SELECT count(*) FROM president
WHERE state = ‘VT’;
SELECT first_name, last_name
FROM president
WHERE state IN (ME,NH,VT,MA,CT,RI);

5. Department of Information Technology 5Data base Technologies (ITB4201)
How to create a DB table?
• Use CREATE TABLE query, specifying fields and column types:
Example:
CREATE TABLE friends (
first_name varchar(25),
last_name varchar(25),
gender enum(‘M’, ‘F’),
grade smallint unsigned,
hair_color varchar(20),
email varchar(30),
screen_name varchar(25),
phone char(12));

6. Department of Information Technology 6Data base Technologies (ITB4201)
Adding records to a table
• Use the INSERT query:
Example:
INSERT INTO friends VALUES (‘Daffy’,
‘Duck’,‘M’,11,’Brunette’,‘daffy@disney.com’,
YellowBill’, ’315-555-1213’);

7. Department of Information Technology 7Data base Technologies (ITB4201)
Editing records
• Use the UPDATE query:
Example:
UPDATE friends
SET phone=‘315-555-1234’
WHERE first_name=‘Daffy’ and
last_name = ‘Duck’;

8. Department of Information Technology 8Data base Technologies (ITB4201)
Deleting records from a table
• Use the DELETE query:
Example:
DELETE FROM friends
WHERE first_name=‘Daffy’ and last_name=‘Duck’;

9. Department of Information Technology 9Data base Technologies (ITB4201)
How to use a DB table?
• Finding a date:
SELECT first_name, screen_name, phone
FROM friends
WHERE gender=‘F’ and
grade > 10 and
hair_color=‘Red’;

10. Department of Information Technology 10Data base Technologies (ITB4201)
Tutorial https://www.techonthenet.com/sql/select.php

11. Department of Information Technology 11Data base Technologies (ITB4201)
Quiz
1. Which of the following SQL clauses is used to DELETE tuples from a database table?
a) DELETE
b) REMOVE
c) DROP
d) CLEAR
2. Which of the following is not a DDL command?
a) UPDATE
b) TRUNCATE
c) ALTER
d) None of the Mentioned
3. The command to remove rows from a table ‘CUSTOMER’ is __________________
a) DROP FROM CUSTOMER
b) UPDATE FROM CUSTOMER
c) REMOVE FROM CUSTOMER
d) DELETE FROM CUSTOMER WHERE
4. With SQL, how do you select all the records from a table named “Persons” where the value of the column “FirstName” ends with
an “a”?
a) SELECT * FROM Persons WHERE FirstName=’a’
b) SELECT * FROM Persons WHERE FirstName LIKE ‘a%’
c) SELECT * FROM Persons WHERE FirstName LIKE ‘%a’
d) SELECT * FROM Persons WHERE FirstName=’%a%’
5. SQL query to find all the cities whose humidity is 95.
a) SELECT city WHERE humidity = 95
b) SELECT city FROM weather WHERE humidity = 95
c) SELECT humidity = 89 FROM weather
d) SELECT city FROM weather

12. Department of Information Technology 12Data base Technologies (ITB4201)
Quiz Answers
1. Which of the following SQL clauses is used to DELETE tuples from a database table?
a) DELETE
b) REMOVE
c) DROP
d) CLEAR
2. Which of the following is not a DDL command?
a) UPDATE
b) TRUNCATE
c) ALTER
d) None of the Mentioned
3. The command to remove rows from a table ‘CUSTOMER’ is __________________
a) DROP FROM CUSTOMER
b) UPDATE FROM CUSTOMER
c) REMOVE FROM CUSTOMER
d) DELETE FROM CUSTOMER WHERE
4. With SQL, how do you select all the records from a table named “Persons” where the value of the column “FirstName” ends with
an “a”?
a) SELECT * FROM Persons WHERE FirstName=’a’
b) SELECT * FROM Persons WHERE FirstName LIKE ‘a%’
c) SELECT * FROM Persons WHERE FirstName LIKE ‘%a’
d) SELECT * FROM Persons WHERE FirstName=’%a%’
5. SQL query to find all the cities whose humidity is 95.
a) SELECT city WHERE humidity = 95
b) SELECT city FROM weather WHERE humidity = 95
c) SELECT humidity = 89 FROM weather
d) SELECT city FROM weather