Aggregate functions

Learn about aggregate functions

Opis Database provides support for most common and widely used aggregate functions.

Counting

PHP

$count = $db->from('users')->count();

echo 'There are ' . $count . ' users registred on this site.';

SQL

SELECT COUNT(*) FROM `users`

Counting all values(NULL values will not be counted) of a column is done by passing the column’s name as an argument to the count method.

PHP

$count = $db->from('users')->count('description');

echo 'There are ' . $count . ' users that have provided a description for their profile.';

SQL

SELECT COUNT(DISTINCT `country`) FROM `users`

Largest value

Finding the largest value of a column is done using the max method. This method accepts the column’s name as an argument.

PHP

$count = $db->from('users')->max('age');

echo 'Our oldest user is ' . $count . ' years old.';

SQL

SELECT MAX(`age`) FROM `users`

Smallest value

Finding the smallest value of a column is done using the min method. This method accepts the column’s name as an argument.

PHP

$count = $db->from('users')->min('age');

echo 'Our youngest user is ' . $count . ' years old.';

SQL

SELECT MIN(`age`) FROM `users`

Average value

Finding the average value of a numeric column is done using the avg method. This method accepts the column’s name as an argument.

PHP

$count = $db->from('users')->avg('age');

echo 'The average age of our users is ' . $count . ' years.';

SQL

SELECT AVG(`age`) FROM `users`

Total sum

Finding the total sum of a numeric column is done using the sum method. This method accepts the column’s name as an argument.

PHP

$count = $db->from('users')->sum('age');

echo 'Our users gathered together ' . $count . ' years of life experience.';

SQL

SELECT SUM(`age`) FROM `users`

Counting