如何在foreach循环中将多维数组推送到另一个多维数组？

When I query in my table and found some rows in my variable in print by foeach loop. Now I want to add another array like array('key' => 'value') to each row just like add another field in table and print by foreach loop

$data = $q -> fetachAll()
$values = array();
foreach($data as $key => $rows) {
    $margeArray = array_merge($rows, array("key" => 'value'));
    array_push($values, $margeArray);
}
/*==Print Here===*/
   foreach($values as $keys => $rows) {
       echo $rows['key'];
   }

How I do that?