<?php

// How much are the salaries of all employees?
$total = Employees::sum(array("column" => "salary"));
// How much are the salaries of all employees in the Sales area?
$total = Employees::sum(array("column" => "salary", "conditions" => "area = 'Sales'"));
// Generate a grouping of the salaries of each area
$group = Employees::sum(array("column" => "salary", "group" => "area"));
foreach ($group as $row) {
    echo "The sum of salaries of the ", $row->area, " is ", $row->sumatory;
}
// Generate a grouping of the salaries of each area ordering
// salaries from higher to lower
$group = Employees::sum(array("column" => "salary", "group" => "area", "order" => "sumatory DESC"));