sql 달력

select x.*, CEIL((x.D_DIFF + x.DAYOFWEEK)/7)||'주' week_name
from (
select sdate,TO_CHAR(TO_DATE(SUBSTR(to_char(sdate,'yyyymmdd'), 1, 6) || '01', 'YYYYMMDD'), 'D') - 1 AS DAYOFWEEK,
TO_NUMBER(to_char(sdate,'yyyymmdd')) - TO_NUMBER(SUBSTR(to_char(sdate,'yyyymmdd'), 1, 6) || '01') AS D_DIFF
from (
 select sysdate + b.rnum as sdate
 from dual, (select rownum rnum
    from   user_tables
    where rownum <=30) b
  )
) x


출처 : http://okjsp.pe.kr/seq/107699