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  • 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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  • 原文地址:https://www.cnblogs.com/ahghy/p/2153388.html
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