ORACLE分頁查詢SQL文法

ORACLE分頁查詢SQL文法 分類： ORACLE專欄 2007-08-26 23:56 4850人閱讀 評論(1) 收藏 舉報

--1:無ORDER BY排序的寫法。(效率最高)
--(經過測試，此方法成本最低，只嵌套一層，速度最快！即使查詢的資料量再大，也幾乎不受影響，速度依然！)
SELECT *
  FROM (Select ROWNUM AS ROWNO, T.*
           from k_task T
          where Flight_date between to_date('20060501', 'yyyymmdd') and
                to_date('20060731', 'yyyymmdd')
            AND ROWNUM <= 20) TABLE_ALIAS
WHERE TABLE_ALIAS.ROWNO >= 10;

--2:有ORDER BY排序的寫法。(效率最高)
--(經過測試，此方法隨著查詢範圍的擴大，速度也會越來越慢哦！)
SELECT *
  FROM (SELECT TT.*, ROWNUM AS ROWNO
           FROM (Select t.*
                    from k_task T
                   where flight_date between to_date('20060501', 'yyyymmdd') and
                         to_date('20060531', 'yyyymmdd')
                   ORDER BY FACT_UP_TIME, flight_no) TT
          WHERE ROWNUM <= 20) TABLE_ALIAS
where TABLE_ALIAS.rowno >= 10;

--3:無ORDER BY排序的寫法。(建議使用方法1代替)
--(此方法隨著查詢資料量的擴張，速度會越來越慢哦！)
SELECT *
  FROM (Select ROWNUM AS ROWNO, T.*
           from k_task T
          where Flight_date between to_date('20060501', 'yyyymmdd') and
                to_date('20060731', 'yyyymmdd')) TABLE_ALIAS
WHERE TABLE_ALIAS.ROWNO <= 20
   AND TABLE_ALIAS.ROWNO >= 10;
--TABLE_ALIAS.ROWNO  between 10 and 100;

--4:有ORDER BY排序的寫法.(建議使用方法2代替)
--(此方法隨著查詢範圍的擴大，速度會越來越慢哦！)
SELECT *
  FROM (SELECT TT.*, ROWNUM AS ROWNO
           FROM (Select *
                    from k_task T
                   where flight_date between to_date('20060501', 'yyyymmdd') and
                         to_date('20060531', 'yyyymmdd')
                   ORDER BY FACT_UP_TIME, flight_no) TT) TABLE_ALIAS
where TABLE_ALIAS.rowno BETWEEN 10 AND 20;

--5另類文法。(有ORDER BY寫法）
--(文法風格與傳統的SQL文法不同，不方便閱讀與理解，為規範與統一標準，不推薦使用。)
With partdata as(
  SELECT ROWNUM AS ROWNO, TT.*  FROM (Select *
                  from k_task T
                 where flight_date between to_date('20060501', 'yyyymmdd') and
                       to_date('20060531', 'yyyymmdd')
                 ORDER BY FACT_UP_TIME, flight_no) TT
   WHERE ROWNUM <= 20)
    Select * from partdata where rowno >= 10;

--6另類文法 。(無ORDER BY寫法）
With partdata as(
  Select ROWNUM AS ROWNO, T.*
    From K_task T
   where Flight_date between to_date('20060501', 'yyyymmdd') and
         To_date('20060531', 'yyyymmdd')
     AND ROWNUM <= 20)
    Select * from partdata where Rowno >= 10;