페이징에 이용되는 ROWNUM

SELECT z.* FROM (
 SELECT
  CEIL(ROW_NUMBER() OVER (ORDER BY NVL(a.p_idx, a.idx) DESC, a.thread DESC)/10) page,
  ROWNUM num,
  a.idx, a.b_id, a.p_idx, a.author_id, a.author_name,
  a.br_cd, TO_CHAR(a.cdate, 'YYYY/MM/DD') cdate, a.subject, a.read_count, a.thread,
  a.h_level, b.first_org_nm AS br_nm
 FROM insa_mansa a, insa_deptview_tbl@insahms b
 WHERE a.br_cd = b.org_cd(+)
 AND b_id = 100
 ORDER BY NVL(a.p_idx, a.idx) DESC, a.thread DESC
) z
WHERE page = 1

강신윤 홈피에서 퍼왔습니다.