Row_Number() Over Order By Computer 列答案

【问题标题】：Row_Number() Over Order By Computer columnRow_Number() Over Order By Computer 列
【发布时间】：2014-05-08 23:07:17
【问题描述】：

我想在 SQL 查询中进行分页和排序。

这是我的查询

;WITH myCTE AS 
(SELECT (FirstName+''+LastName) as [User Name],
         ROW_NUMBER() OVER (ORDER BY FirstName) as RowID
         From [MyTable]) 

SELECT TOP 10 * FROM myCTE
    WHERE RowID > 10*(2-1)

工作正常，但现在我想按计算列 [用户名]

对记录进行排序

所以我改变了这样的查询

;WITH myCTE AS 
(SELECT (FirstName+''+LastName) as [User Name],
         ROW_NUMBER() OVER (ORDER BY [User Name] ASC) as RowID
         From [MyTable]) 

SELECT TOP 10 * FROM myCTE
    WHERE RowID > 10*(2-1)

但它给出了这个错误：

Msg 207, Level 16, State 1, Line 2
Invalid column name 'User Name'.

谁能帮助我如何使用 ROW_NUMBER() OVER 计算列？或者如何在SQL查询中实现对记录的排序和分页？

【问题讨论】：

标签： sql sql-server sql-server-2008 tsql sql-server-2005

【解决方案1】：

只引用order by中的实际表达式，而不是别名：

;WITH myCTE AS 
(SELECT (FirstName+''+LastName) as [User Name],
         ROW_NUMBER() OVER (ORDER BY FirstName+''+LastName ASC) as RowID
         From [MyTable]) 

SELECT TOP 10 * FROM myCTE
    WHERE RowID > 10*(2-1)

【讨论】：

【解决方案2】：

DECLARE @pageNumber int,
        @page_Size int,
        @page_start int

SET @pageNumber = 1
SET @page_Size = 10
SET @page_start = ((@page_Size-1) * @pageNumber) + 1
Select TOP(@page_Size)<valiables_names>,ROW_NUMBER() [Row_ID] from <table_Name> having Row_ID >= @page_start

【讨论】：

【解决方案3】：

两件事。首先，您不能在同一 SELECT 子句中引用其他列，因为所有列都是“并行”有效计算的，因此新创建的值不可用。一种方法是重复 Ian 的answer 显示的表达式，另一种方法是引入另一个 CTE：

;WITH CombinedNames AS 
(
    SELECT (FirstName+''+LastName) as [User Name]
    FROM MyTable
), Numbered as
(
    SELECT [User Name],
         ROW_NUMBER() OVER (ORDER BY [User Name]) as RowID
         From CombinedNames
) 
SELECT TOP 10 * FROM Numbered
    WHERE RowID > 10*(2-1)

但是，这很重要，这实际上仍然是坏的。为什么？因为您没有将任何 ORDER BY 应用到使用 TOP 选择 10 行的最终 SELECT - 所以您没有得到“应该出现在第 2 页上的 10 行”，而是得到“任何随机 10 行未出现在第 1 页上”。所以我们需要做出另一个改变：

;WITH CombinedNames AS 
(
    SELECT (FirstName+''+LastName) as [User Name]
    FROM MyTable
), Numbered as
(
    SELECT [User Name],
         ROW_NUMBER() OVER (ORDER BY [User Name]) as RowID
         From CombinedNames
) 
SELECT TOP 10 * FROM Numbered
    WHERE RowID > 10*(2-1)
ORDER BY RowID

或者如果您愿意：

;WITH CombinedNames AS 
(
    SELECT (FirstName+''+LastName) as [User Name]
    FROM MyTable
), Numbered as
(
    SELECT [User Name],
         ROW_NUMBER() OVER (ORDER BY [User Name]) as RowID
         From CombinedNames
) 
SELECT TOP 10 * FROM Numbered
    WHERE RowID > 10*(2-1) AND RowID <= 10*2

但请注意，第二个变体不保证页面内返回结果的顺序。

【讨论】：