select day1, count(*)
  from (
  SELECT TO_DATE('20120209','yyyymmdd') + LEVEL - 1 dt
       , TO_CHAR(TO_DATE('20120209','yyyymmdd') + LEVEL - 1, 'day') day1
       , TO_CHAR(TO_DATE('20120209','yyyymmdd') + LEVEL - 1, 'd') day2
    FROM dual
  CONNECT BY LEVEL <= TO_DATE('20120219','yyyymmdd') - TO_DATE('20120209','yyyymmdd') + 1
       )
 group by day1, day2
 order by day2
 

WITH t AS
(
SELECT TO_DATE('20120209', 'yyyymmdd') sdt
     , TO_DATE('20120219', 'yyyymmdd') edt
     , '일' dy
  FROM dual
)
SELECT sdt, edt, dy
     , CEIL((edt - NEXT_DAY(sdt - 1, dy) + 1) / 7) dy_cnt
  FROM t
;

정말 감사합니다. 많이 고민했는데~

유용하게 쓰겠습니다. ^^