MySQL - MAX() Function


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In general, aggregation is a consideration of a collection of objects that are bound together as a single entity.

MySQL provides a set of aggregate functions that perform operations on all the entities of the column of a table considering them as a single unit.

The MySQL Max() function is used to retrieve the maximum value among the fields in a particular column. If the specified row(s) doesn’t exist this function returns NULL.

If you use the DISTINCT keyword, this function returns the maximum of the unique values of the given column –

Syntax

Following is the syntax of this function –

MAX(expr);

Example 1

Following is an example demonstrating the usage of this function. Assume we have created a table with name MyPlayers in MySQL database using CREATE statement as shown below –

mysql> CREATE TABLE MyPlayers(
	ID INT,
	First_Name VARCHAR(255),
	Last_Name VARCHAR(255),
	Socre_In_Exhibiiton_match INT,
	COUNTRY VARCHAR(100),
	PRIMARY KEY (ID)
);

This table stores the first and last names, country, scores in an exhibition match of a player. Now, we will insert 7 records in MyPlayers table using INSERT statements −

insert into MyPlayers values(1, 'Shikhar', 'Dhawan', 95, 'India');
insert into MyPlayers values(2, 'Jonathan', 'Trott', 50, 'SouthAfrica');
insert into MyPlayers values(3, 'Kumara', 'Sangakkara', 25, 'Sri Lanka');
insert into MyPlayers values(4, 'Virat', 'Kohli', 50, 'India');
insert into MyPlayers values(5, 'Rohit', 'Sharma', 25, 'India');
insert into MyPlayers values(6, 'Ravindra', 'Jadeja', 15, 'India');
insert into MyPlayers values(7, 'James', 'Anderson', 15, 'England');

Following query calculates the maximum score among all the players in an exhibition match –

mysql> SELECT MAX(Socre_In_Exhibiiton_match) from MyPlayers;
+--------------------------------+
| MAX(Socre_In_Exhibiiton_match) |
+--------------------------------+
|                             95 |
+--------------------------------+
1 row in set (0.08 sec)

Example 2

Following is another example of this function. Assume we have created another table named employee_tbl and inserted records in it as follows –

mysql> CREATE TABLE employee_tbl (
	id INT,
	name VARCHAR(255),
	Work_date INT,
	daily_typing_pages INT
);
mysql> insert into employee_tbl values(1, John, DATE('2007-01-24'), 250);
mysql> insert into employee_tbl values(2, 'Ram', DATE('2007-05-27'), 220);
mysql> insert into employee_tbl values(3, 'Jack', DATE('2007-05-06'), 170);
mysql> insert into employee_tbl values(3, 'Jack', DATE('2007-04-06'), 100);
mysql> insert into employee_tbl values(4, 'Jill', DATE('2007-04-06'), 220);
mysql> insert into employee_tbl values(5, 'Zara', DATE('2007-06-06'), 300);
mysql> insert into employee_tbl values(5, 'Zara', DATE('2007-02-06'), 350);

Now, suppose based on the above table you want to fetch maximum value of daily_typing_pages, then you can do so simply using the following command −

mysql> SELECT MAX(daily_typing_pages) FROM employee_tbl;
+-------------------------+
| MAX(daily_typing_pages) |
+-------------------------+
|                     350 |
+-------------------------+
1 row in set (0.00 sec)

You can find all the records with maximum value for each name using GROUP BY clause as follows −

mysql> SELECT id, name, MAX(daily_typing_pages) FROM employee_tbl GROUP BY name;
+------+------+-------------------------+
| id   | name | MAX(daily_typing_pages) |
+------+------+-------------------------+
| 2    |  Ram |                     220 |
| 3    | Jack |                     170 |
| 4    | Jill |                     220 |
| 5    | Zara |                     350 |
| 1    | John |                     250 |
+------+------+-------------------------+
5 rows in set (0.00 sec)

Example 3

Let us create a table named student and inserted records into it using CREATE and INSERT statements as shown below –

mysql> CREATE TABLE student (name VARCHAR(15), marks INT, grade CHAR);
mysql> INSERT INTO student VALUES ('Raju', 80, 'A');
mysql> INSERT INTO student VALUES ('Rahman', 60, 'B');
mysql> INSERT INTO student VALUES ('Robert', 45, 'C');

Following query prints the maximum value of the marks column of the student table –

mysql> SELECT MAX(marks) from student;
+------------+
| MAX(marks) |
+------------+
|         60 |
+------------+
1 row in set (0.03 sec)

Example 4

Assume we have created and populated a table with name Sales.

mysql> CREATE TABLE sales(
	ID INT,
	ProductName VARCHAR(255),
	CustomerName VARCHAR(255),
	DispatchDate date,
	DeliveryTime time,
	Price INT,
	Location VARCHAR(255)
);
Query OK, 0 rows affected (2.22 sec)
INSERT INTO SALES values(1, 'Key-Board', 'Raja', DATE('2019-09-01'), TIME('11:00:00'), 7000, 'Hyderabad');
INSERT INTO SALES values(2, 'Earphones', 'Roja', DATE('2019-05-01'), TIME('11:00:00'), 2000, 'Vishakhapatnam');
INSERT INTO SALES values(3, 'Mouse', 'Puja', DATE('2019-03-01'), TIME('10:59:59'), 3000, 'Vijayawada');
INSERT INTO SALES values(4, 'Mobile', 'Vanaja', DATE('2019-03-01'), TIME('10:10:52'), 9000, 'Chennai');
INSERT INTO SALES values(5, 'Headset', 'Jalaja', DATE('2019-04-06'), TIME('11:08:59'), 6000, 'Goa');

Following query prints the maximum value of the Price column –

mysql> SELECT MAX(Price) FROM SALES;
+------------+
| MAX(Price) |
+------------+
|       9000 |
+------------+
1 row in set (0.00 sec)
mysql-aggregate-functions.htm
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