/**
* Construct the ORDER BY clause.
*
* We override this to ensure that XP set to null appears at the bottom, not the top.
*
* @param array $cols The columns.
* @param array $textsortcols The text columns.
* @return string
*/
public static function construct_order_by($cols, $textsortcols = array())
{
$newcols = array();
// We use a foreach to maintain the order in which the fields were defined.
foreach ($cols as $field => $sortorder) {
if ($field == 'xp') {
$field = 'COALESCE(xp, 0)';
}
$newcols[$field] = $sortorder;
}
return parent::construct_order_by($newcols, $textsortcols);
}
