用于XML名称输出列的SQL UNION

Question

我试图从SQL生成XML输出，并且需要使用UNION语句并命名输出列。

我时，我并不需要使用使用UNION语句之前这方面的工作：

select(
SELECT 

    [CompanyName], 
    [Address1], 
    [Address2], 
    [Address3], 
    [Town], 
    [County], 
    [Postcode], 
    [Tel], 
    [Fax], 
    [Email], 
    [LocMap] 

FROM [UserAccs] FOR XML PATH ('AccountDetails'), root ('Root') 
) as XmlOutput 

哪个命名输出XML列XmlOutput

我现在想：

select(
SELECT 

    [CompanyName], 
    [Address1], 
    [Address2], 
    [Address3], 
    [Town], 
    [County], 
    [Postcode], 
    [Tel], 
    [Fax], 
    [Email], 
    [LocMap] 

FROM [UserAccs] 

UNION 

SELECT 

    [CompanyName], 
    [Address1], 
    [Address2], 
    [Address3], 
    [Town], 
    [County], 
    [Postcode], 
    [Tel], 
    [Fax], 
    [Email], 
    [LocMap] 

FROM [UserAppAccs] 



FOR XML PATH ('AccountDetails'), root ('Root') 
) as XmlOutput 

但收到一条错误消息，有没有人知道解决这个问题的方法？

The FOR XML clause is invalid in views, inline functions, derived tables, and subqueries when they contain a set operator. To work around, wrap the SELECT containing a set operator using derived table syntax and apply FOR XML on top of it. 

感谢 J.

Answer 1

包裹在一个单一的2个选择，然后做：

select (
    select id, name from (
     select id, name 
     from xmltest 
     UNION 
     select id, name 
     from xmltest 
) A 
FOR XML PATH ('AccountDetails'), root ('Root') 
) As XmlOutput