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  • row_number over ()排序函数

    语法: row_number () over (排序规则)  计算每一行数据在结果集的行数

    select ROW_NUMBER() over (order by FSalary) as 排序 ,*  from T_Employe 

    查询前五条数据, 并显示行号

    select top 5  * from
    (select ROW_NUMBER() over(order by FSalary)as rownum ,*  from T_Employee )as a

    row_number ()只能出现在 select , order by子句中, 不能用在where语句中,

    比如: 返回第三行和第五行的数据

    select ROW_NUMBER() over (order by FSalary ),* from T_Employee  
    where (ROW_NUMBER()over (order by FSalary ))>=3 

       and  (ROW_NUMBER()over (order by FSalary ))<=5

    这样写 , 则会提示:开窗函数只能出现在 SELECT 或 ORDER BY 子句中。

    因此: 可以使用子查询,如下

    select *from (
    select  row_number()over(order by FSalary) as rownum ,* from T_Employee
    )as a where rownum >=3 and rownum<=5

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  • 原文地址:https://www.cnblogs.com/lucky9/p/6264340.html
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