Sorts a multidimensional array by value given the key name

multidimensional_array_sort_by_value

$arrayItems = array(
	array ("date" => "2018-10-21", "grade" => 50),
	array ("date" => "2018-04-02",  "grade" =>88),
	array ("date" => "2018-03-17",  "grade" =>76),
	array ("date" => "2018-03-10",  "grade" =>84),
	array ("date" => "2019-02-03",  "grade" =>67),
);

// Obtain a list of columns - last value is the key
$myCols  = array_column($arrayItems, 'date');
array_multisort($myCols, SORT_DESC, $arrayItems);
print_r($arrayItems);