Снятие логгирования на индексах пользователя : Oracle

BEGIN
FOR c IN (SELECT owner,index_name FROM dba_indexes WHERE owner='SUPERMAG')
LOOP
BEGIN
EXECUTE IMMEDIATE
'alter index '||c.owner||'.' || c.index_name || ' nologging';
EXCEPTION WHEN OTHERS THEN BEGIN
dbms_output.put_line(c.owner||'.' || c.index_name);
END;
END;
END LOOP;
END;
/