Array
(
    [ID] => 4
    [DATE_CREATE] => 04.10.2013 20:47:52
    [NAME] => BCAA
    [DEPTH_LEVEL] => 1
    [DESCRIPTION] =>
    [SEARCHABLE_CONTENT] => BCAA
    [CODE] => bcaa
    [DETAIL_PICTURE] =>
)

Array
(
    [ID] => 4
    [DATE_CREATE] => 04.10.2013 20:47:52
    [NAME] => BCAA
    [DEPTH_LEVEL] => 1
)

$arr = array('id' => 4, 'date_create' => '4.10.2013 20:47:52', 'name' => 'BCAA', 'depth_level' => 1, 'description' => null, 'searchable_content' => 'BCAA', 'code' => 'BCAA', 'detail_picture' => null);
$delete_keys = array('description', 'searchable_content', 'code', 'detail_picture');
$new_arr = array();
foreach ($arr as $key => $value) {
    if (!in_array($key, $delete_keys)) {
        $new_arr[$key] = $value;
    }
}

$arr = array('id' => 4, 'date_create' => '4.10.2013 20:47:52', 'name' => 'BCAA', 'depth_level' => 1, 'description' => null, 'searchable_content' => 'BCAA', 'code' => 'BCAA', 'detail_picture' => null);
$delete_keys = array('description', 'searchable_content', 'code', 'detail_picture');
foreach ($arr as $key => $value) {
    if (in_array($key, $delete_keys)) {
        unset($arr[$key]);
    }
}

$arr = array('id' => 4, 'date_create' => '4.10.2013 20:47:52', 'name' => 'BCAA', 'depth_level' => 1, 'description' => null, 'searchable_content' => 'BCAA', 'code' => 'BCAA', 'detail_picture' => null);
$delete_keys = array('description', 'searchable_content', 'code', 'detail_picture');

$arr = array_diff_key($arr, array_flip($delete_keys)); // Only one line!

$old_array = array('ID' => '4', 'DATE_CREATE' => '04.10.2013 20:47:52', 'NAME' => 'BCAA', 'DEPTH_LEVEL' => '1', 'DESCRIPTION' => '', 'SEARCHABLE_CONTENT' => 'BCAA', 'CODE' => 'bcaa', 'DETAIL_PICTURE' => '');

$new_array = array('ID' => '', 'DATE_CREATE' => '', 'NAME' => '', 'DEPTH_LEVEL' => '');

$new_array = array_intersect_key($old_array, $new_array);

$columns = array_diff_key($columns, array_flip([
    'ID',
    'DATE_CREATE',
    'NAME',
    'DEPTH_LEVEL',
]));