1. MySQL DML Commands By Prof. B.A.Khivsara
Note: The material to prepare this presentation has been taken from internet and are generated only for students reference and not for commercial use.

2. Design at least 10 SQL queries for suitable database application using SQL DML statements
Insert,
Select,
Update,
Delete
with operators,
functions and
set operator.

3. Insert - INSERT tuples into a relation
Where every attribute in the table is given a value
INSERT INTO tablename
VALUES (attr1_value, attr2_value, ... attrn_value)
Where every attribute in the table is has not a value then it considered as NULL. INSERT INTO tablename (attrx, ... , attry)
VALUES (attrx_value, ... , attry_value)
Example:
Insert into Stud values (1,’Pooja’, ‘Pune’)
Insert into Stud (rollno,name) values (2, ‘Amit’)
The output of "Stud" table after inserting above 2 rows
rollno
Name
Address 1
Pooja
Pune 2
Amit

4. Delete –DELETE tuples from relation
Syntax
DELETE FROM tablename <WHERE condition>
It removes zero, one or many tuples; The WHERE clause is optional; if it is left out all tuples are removed, but the table still exists; it is empty.
Example:
1> DELETE FROM Stud WHERE Address = 'Pune';
( Only delete roes that satisfy the condition)
2> DELETE FROM Stud;
(Delete all rows)

5. Update- UPDATE of one or more selected tuples
Syntax
UPDATE tablename
SET attrx = new_value,
<WHERE condition>;
Example:
1> Update Stud Set Name= ‘Shruti’ where rollno=1
(Only name field of row having rollno as 1 will be chaged as ‘Shruti’)
2> Update Stud Set Name= ‘Shruti’
(name field of All row will be changed as ‘Shruti’)

6. Select- SELECT statement retrieves data from table
Syntax
SELECT attribute_list
FROM table_list
<WHERE condition>;
The attributes are those you want to see in the result,
the tables are those required for the query,
the condition is a boolean expression that specifies which tuples are to be retrieved by the query.
Example:
Select * from Stud;
Select * from Stud where rno=1;
Select Name, Address from Stud;
Select Name, Address from Stud where rno=1
Select Name from Stud where address=‘Nashik’;

7. Order By- Retrieval with ordering Ascending/ Descending
The ORDER BY keyword is used to sort the result-set by a specified column.
The ORDER BY keyword sort the records in ascending order by default.
If you want to sort the records in a descending order, you can use the DESC keyword.
Syntax
SELECT column_name(s) FROM table_name ORDER BY column_name(s) ASC|DESC
Example
Select * from Stud order by rno desc;
Select * from Stud order by rno ;
Select * from Stud order by Name;

8. LIKE Operator- search for a specified pattern in a column
Syntax
SELECT column_name(s) FROM table_name WHERE column_name LIKE pattern
SQL Wildcards 
SQL wildcards can substitute for one or more characters when searching for data in a database.
SQL wildcards must be used with the LIKE operator.
Wildcard
Description %
A substitute for zero or more characters _
A substitute for exactly one character

9. LIKE Operator- Example
"Persons" table
P_Id
LastName
Address 1
Heena
Pune 2
Savita 3
Sarika
Bombay
We use the following SELECT statement:
SELECT LastName from Person where LastName like ‘S%’ ;
The result-set will look like this:
LastName
Savita
Sarika

10. DISTINCT Operator Syntax Example
The DISTINCT keyword can be used to return only distinct (different) values.
Syntax
SELECT DISTINCT column_name(s) FROM table_name
Example
SELECT distinct(Address) from Person
The result-set will look like this
The "Persons" table:
P_Id
Name
Address 1
Hansen
Pune 2
Svendson 3
Pettersen
Bombay
Address
Pune
Bombay

11. IN Operator- The IN operator allows you to specify multiple values in a WHERE clause.
Syntax
SELECT column_name(s) FROM table_name WHERE column_name IN (value1,value2,...)
Example
SELECT * FROM Persons WHERE Address IN ('Pune','Bombay')
The result-set will look like this
The "Persons" table:
P_Id
Name
Address 1
Hansen
Pune 2
Svendson
Nashik 3
Pettersen
Bombay
P_Id
Name
Address 1
Hansen
Pune 3
Pettersen
Bombay

12. NULL Operator- Syntax Example
To test if a value is NULL you cannot use =, because every NULL is considered distinct from every other one. Must use "IS NULL" or "IS NOT NULL“
Syntax
SELECT Attr_List FROM table_name
WHERE Attr_name IS NULL;
Example
SELECT * FROM Stud WHERE Address is null;
SELECT * FROM Stud WHERE Address is not null;

13. Aggregate Functions
Aggregate /Group functions are built-in SQL functions that operate on groups of rows and return one value for the entire group.
The Functions are as below:
MIN
returns the smallest value in a given column
MAX
returns the largest value in a given column
SUM
returns the sum of the numeric values in a given column
AVG
returns the average value of a given column
COUNT
returns the total number of values in a given column
COUNT(*)
returns the number of rows in a table

14. Count()- Syntax
COUNT(column_name)-The COUNT(column_name) function returns the number of values (NULL values will not be counted) of the specified column:
Syntax
SELECT COUNT(column_name) FROM table_name
COUNT(*)-The COUNT(*) function returns the number of records in a table:
SELECT COUNT(*) FROM table_name

15. Count()- Example Consider an employee_tbl table as shown below
SELECT COUNT(*) FROM employee_tbl ;
SELECT COUNT(*) FROM employee_tbl WHERE name="Zara";
Output
Count(*) 7
Output
Count(*) 2

16. Avg(),Min(),Max(),Sum()
Syntax
SELECT AVG(column_name) FROM table_name
Example
SELECT AVG(Marks) FROM Stud
SELECT Min(column_name) FROM table_name
SELECT Min(Marks) FROM Stud
Syntax of all other functions are similar.

17. GROUP BY & Having Clause
The SQL GROUP BY clause is used in collaboration with the SELECT statement to arrange identical data into groups. This GROUP BY clause follows the WHERE clause in a SELECT statement
Having is similar to where, to give condition, but it can only work with group by
Syntax
SELECT column_name(s) FROM table_name WHERE condition GROUP BY column_name(s)
HAVING condition ;

18. GROUP BY & Having Clause- Example
Products Table id
name
type
price
123451
Park's Great Hits
Music 19
123452
Silly Puddy
Toy 5
123453
Playstation 89
123454
Men's T-Shirt
Clothing 32
123455
Blouse 34
123456
Electronica 2002 3
SELECT type, MIN(price) FROM products GROUP BY type
SELECT type, Min(price) FROM products GROUP BY type having Min(price)>4
Type
Min(Prize)
Music 3
Toy 5
Clothing 32
Type
Min(Prize)
Toy 5
Clothing 32
Out Put

19. Set Operator: UNION,UNION ALL
UNION operator displays the combined result from all the compounded SELECT queries, after removing all duplicates and in sorted order (ascending by default), without ignoring the NULL values.
UNION ALL gives the result set without removing duplication and sorting the data.

20. Set Operator- Example Union and Union all
ENo
Ename
Addr
101
Jenny
Mumbai
102
Akash
Pune
103
Sona
104
Minal
Nashik
105
Raksh
Jalgoan
Emp
Table
Proj
Table
PrNo
Addr 10
Mumbai 20
Pune 30
Addr
Jalgoan
Mumbai
Nashik
Pune
Addr
Jalgoan
Mumbai
Nashik
Pune
SELECT City FROM Emp
UNION All SELECT City FROM Proj
ORDER BY City;
SELECT City FROM Emp
UNION SELECT City FROM Proj
ORDER BY City;
O/P
O/P

21. Assignment
Create Employee table, Project table and add rows shown below
Eid
EName
Address
Salary
Commision 1
Amit
Pune
35000
5000 2
Sneha
25000 3
Savita
Nasik
28000
2000 4
Pooja
Mumbai
19000 5
Sagar
3000
PrNo
Addr 10
Mumbai 20
Pune 30
Jalgoan
Find different locations from where employees belong to?
What is maximum and minimum salary?
Display the content of employee table according to the ascending order of salary amount.
Find the name of employee who lived in Nasik or Pune city.
Find the name of employees who does not get commission.
Change the city of Amit to Nashik.
Find the information of employees whose name starts with ‘A’.
Find the count of staff from Mumbai.
Find the count of staff from each city
Find the address from where employees are belonging as well as where projects are going on.
Find city wise minimum salary.
Find city wise maximum salary having maximum salary greater than 26000
Delete the employee who is having salary greater than 30,000.

22. References https://www.tutorialspoint.com/mysql/