MS SQL 2005 - 使用子查询进行排序失败

Question

这是真实查询的简化版本，用于显示问题。它可以在示例 Adventureworks 数据库上执行：

SELECT Person.Address.*,
 (SELECT TOP 1 [Name]
 FROM Person.StateProvince
 WHERE Person.StateProvince.StateProvinceId = Person.Address.StateProvinceId AND Person.StateProvince.TerritoryId IN (5, 6, 7)
 ORDER BY Person.StateProvince.TerritoryId) AS [Name]
FROM Person.Address
ORDER BY [Name]

这效果很好，但我的问题是，如果我向 order by 字段添加排序规则，我会收到一条奇怪的错误消息：

SELECT Person.Address.*,
 (SELECT TOP 1 [Name]
 FROM Person.StateProvince
 WHERE Person.StateProvince.StateProvinceId = Person.Address.StateProvinceId AND Person.StateProvince.TerritoryId IN (5, 6, 7)
 ORDER BY Person.StateProvince.TerritoryId) AS [Name]
FROM Person.Address
ORDER BY [Name] COLLATE Chinese_PRC_CI_AI

错误是：

Msg 207, Level 16, State 1, Line 7
Invalid column name 'Name'.

带有 collat​​e 子句的查询运行良好，如果没有子查询，但我需要它像这样（出于复杂的原因，但请相信我:)）。

有谁知道为什么这个查询失败，以及可能的解决方法是什么？这是一个错误吗？

谢谢！ 亚当

Answer 1

SQL Server 不允许您在 order by 子句中通过别名引用列。例如，这不起作用：

select id+1 as x from MyTable order by x

但您可以通过重复列定义来修复该问题：

select id+1 as x from MyTable order by id+1

或者使用子查询：

select * from (select id+1 as x from MyTable) as subquery order by x

在您的情况下，最好的修复可能是使用子查询：

SELECT  *
FROM    (
        SELECT  Person.Address.*
        ,       (
                SELECT  TOP 1 [Name]
                FROM    Person.StateProvince
                WHERE   Person.StateProvince.StateProvinceId = 
                            Person.Address.StateProvinceId 
                        AND Person.StateProvince.TerritoryId IN (5, 6, 7)
                ORDER BY 
                        Person.StateProvince.TerritoryId
                ) AS [Name]
        FROM    Person.Address
        ) as SubqueryAlias
ORDER BY 
        [Name]