Sorting Model data with usort()

For example, if you want to achive like this:

Controller -------------------
$data1 = $this->Reservation->findAll();
$data2 = $this->AdditionalReservation->findAll();

//If needed, change $data2's array name
 "AdditionalReservation" to "Reservation". Then,

$data = array_merge($data1, $data2);

$data = $this->Reservation->sortbytime($data);
$this->set("reservations", $data);
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You can use this technique.

Model ------------------------
function myCmp($array1, $array2)
{
    $time1 = strtotime($array1['Reservation']['rsv_time']);
    $time2 = strtotime($array2['Reservation']['rsv_time']);
    if($time1 == $time2){
        return 0;
    }
    return ($time1 > $time2)? 1 : -1;
}

function sortbytime($data)
{
    usort($data, array("Reservation", "myCmp"));
    return $data;
}
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