MySQL Aggregate Functions - MIN()
This lesson will teach you how to use the aggregate function
MIN(). If you missed the
Aggregate Introduction Lesson
, you might want to check it
out to learn about the GROUP BY statement and its use with MySQL
aggregate functions.
You can download the table used in this example,
products.sql
, from our website. A SQL file can be run
through your MySQL administrator interface to create the table.
However, if you would like to create the table with
PHP/MySQL, check out our
Create a MySQL Table
and
Insert a MySQL Row
lessons.
Products Table:
| id |
name |
type |
price |
| 123451 |
Park's Great Hits |
Music |
19.99 |
| 123452 |
Silly Puddy |
Toy |
3.99 |
| 123453 |
Playstation |
Toy |
89.95 |
| 123454 |
Men's T-Shirt |
Clothing |
32.50 |
| 123455 |
Blouse |
Clothing |
34.97 |
| 123456 |
Electronica 2002 |
Music |
3.99 |
| 123457 |
Country Tunes |
Music |
21.55 |
| 123458 |
Watermelon |
Food |
8.73 |
MySQL MIN
The MIN function is an aggregate function that finds the
smallest value in a group. The products table that is displayed
above has several products of various types. One use of MIN
might be to find out the cheapest item in each group.
Just as we did in the
Aggregate Introduction Lesson
, we are going to GROUP BY
type
to create four groups: Music, Toy, Clothing and Food.
The column that will have the MIN function applied to it is, of
course, price.
PHP and MySQL Code:
<?php
// Make a MySQL Connection
$query = "SELECT type, MIN(price) FROM products GROUP BY type";
$result = mysql_query($query) or die(mysql_error());
// Print out result
while($row = mysql_fetch_array($result)){
echo "The cheapest ". $row['type']. " is $" .$row['MIN(price)'];
echo "<br />";
}
?>
Display:
The cheapest Clothing is $32.50
The cheapest Food is $8.73
The cheapest Music is $3.99
The cheapest Toy is $3.99
|