SELECT to_char(dt_giorno, 'DAY') ds_giorno, dt_giorno
  FROM (SELECT TO_DATE(TO_CHAR(LEVEL, '09') 
          ||
          TO_CHAR(EXTRACT(MONTH FROM to_date('201301' || '01', 'YYYYMMDD')), '09') 
          || 
          TO_CHAR(EXTRACT(YEAR FROM to_date('201301' || '01', 'YYYYMMDD')), '9999'), 
          'DDMMYYYY') dt_giorno
          FROM dual
         WHERE ROWNUM <= EXTRACT(DAY FROM LAST_DAY(to_date('201301' || '01', 
                         'YYYYMMDD')))
               CONNECT BY LEVEL = ROWNUM)
 ORDER BY dt_giorno