function getMemberOf($rolename)
{
$this->clean($rolename);
$sql = "\n\t\t\tSELECT rolname FROM pg_catalog.pg_roles R, pg_auth_members M\n\t\t\tWHERE R.oid=M.roleid\n\t\t\t\tAND member IN (\n\t\t\t\t\tSELECT oid FROM pg_catalog.pg_roles\n\t\t\t\t\tWHERE rolname='{$rolename}')\n\t\t\tORDER BY rolname";
return $this->selectSet($sql);
}