function getReferencingTable($table, $column, $active = NULL, $forceNewInstance = FALSE)
{
$referencing =& $this->referencing["{$table}:{$column}"];
if (!$referencing || $forceNewInstance) {
$referencing = new GroupedSelection($table, $this, $column);
$referencing->where("{$table}.{$column}", array_keys((array) $this->rows));
}
return $referencing->setActive($active);
}