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  • Oracle分页查询和SQL server分页查询总结

    分页查询是项目中必不可少的一部分,难倒是不难,就是这些东西,长时间不用,就忘的一干二净了。今天特此总结一下这两款数据库分页查询的实现过程(只记录效率比较高的)

    一.Oracle中的分页查询

      1.通用分页查询模板

     SELECT *
            FROM (SELECT x.*, rownum as m FROM ({0}) x)    --{0}为嵌套的查询语句或为一张表
           WHERE m >= {1}                                  --{1}取值的最小范围    
             AND m <= {2}                                  --{2}取值的最大范围

       查询的原理是,先用一个子查询,将查询得到的数据进行排列,最外层的查询再根据rownum取范围,下面贴一个实例,方便以后查看

         SELECT *
            FROM (SELECT x.*, rownum as r FROM (
              select c.* from Cars c join ResCommend r on c.Id=r.ResId where r.Posld=2 and DeadLine>SYSDATE and c.IsPub=''   order by r.Weight desc
                      ) x)
           WHERE r >= 0
             AND r <= 6
                      

    二.Sqlserver中的分页查询

      1.用row_number() over()进行分页

                   select * 
                       from (select row_number() over(order by Weight desc) as rownumber,* from ({0}) as hello) as newtable   --{0}为嵌套的查询语句或为一张表
                            where rownumber>={1}                                                                       --{1}取值的最小范围    
                              and rownumber<={2}                                                                     --取值的最大范围

       查询的原理是,先用row_number()将查询到的数据进行排列,最外层的查询再根据rownumber取范围,下面贴一个实例

              select * from (select row_number() over(order by Weight desc) as rownumber,* from (
               select c.*,r.Weight from Cars c join ResCommend r on c.Id=r.ResId where r.Posld=2 and DeadLine>GETDATE() and c.IsPub=''  
                      ) as hello) as newtable where rownumber>=0 and rownumber<=6
                      

      

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  • 原文地址:https://www.cnblogs.com/HTLucky/p/11947734.html
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