日期 星期

select to_char(t.d, 'yyyymmdd'), to_char(t.d, 'day')
  from (SELECT to_date('20130131', 'YYYYMMDD') - ROWNUM + 1 D
          FROM USER_OBJECTS
         WHERE ROWNUM <= to_date('20130131', 'YYYYMMDD') -
               TO_DATE('20130101', 'YYYYMMDD')) t