• Oracle实现分页查询的SQL语法汇总


    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!

    sql语句如下:

    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!

    sql语句如下:

    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!

    sql语句如下:

    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,速度也会越来越慢!

    sql语句如下:

    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)

    该语法风格与传统的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。此处贴出代码供大家参考之用。

    sql语句如下:

    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;

    相信本文所述代码能够对大家有一定的参考借鉴价值。

  • 相关阅读:
    Apache Tomcat Ajp CVE-2020-1938漏洞复现
    关于JDK高版本下RMI、LDAP+JNDI bypass的一点笔记
    javaweb-codereview 学习记录-5
    java 动态代理机制
    关于<Java 中 RMI、JNDI、LDAP、JRMP、JMX、JMS那些事儿(上)>看后的一些总结-2
    关于<Java 中 RMI、JNDI、LDAP、JRMP、JMX、JMS那些事儿(上)>看后的一些总结-1
    javaweb-codereview 学习记录-4
    从0到1掌握某Json-TemplatesImpl链与ysoserial-jdk7u21的前因后果
    javaweb-codereview 学习记录-2
    javaweb-codereview 学习记录-1
  • 原文地址:https://www.cnblogs.com/laoyeye/p/6340431.html
Copyright © 2020-2023  润新知