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Oracle教程:ORACLE分页查询SQL源代码

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Oracle教程:ORACLE分页查询SQL源代码
Oracle教程:ORACLE分页查询SQL源代码Oracle
【51Test.NET-Oracle教程:ORACLE分页查询SQL源代码】:
--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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