ORACLE分页查询SQL语法

ORACLE分页查询SQL语法

分类: ORACLE专栏 4850人阅读 评论(1) 收藏 举报

--1:无ORDER BY排序的写法。(效率最高)
--(经过测试,此方法成本最低,只嵌套一层,速度最快!即使查询的数据量再大,也几乎不受影响,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排序的写法。(效率最高)
--(经过测试,此方法随着查询范围的扩大,速度也会越来越慢哦!)
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:无ORDER BY排序的写法。(建议使用方法1代替)
--(此方法随着查询数据量的扩张,速度会越来越慢哦!)
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排序的写法.(建议使用方法2代替)
--(此方法随着查询范围的扩大,速度会越来越慢哦!)
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另类语法。(有ORDER BY写法)
--(语法风格与传统的SQL语法不同,不方便阅读与理解,为规范与统一标准,不推荐使用。)
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另类语法 。(无ORDER BY写法)
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;   

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