无法解决SQL Server 2014中SELECT语句中第3列的排序规则冲突

Question

我有一张桌子＆＃39; CustomerAccount＆＃39;包含以下字段：

1. 账户号码
2. AmountDue
3. 公司名称
4. Cust_FirstName
5. Cust_LastName
6. 地址

我正在尝试提取一份简单的报告，但收到错误消息。我似乎无法弄清楚出了什么问题。

我的代码：

SELECT AccountNumber
      ,AmountDue
      --,ISNULL(Cust_LastName, '') + ', ' + ISNULL(Cust_FirstName, '') CustomerName
      ,CASE WHEN ISNULL(CompanyName, '') = '' 
            THEN Cust_LastName + ', ' + Cust_FirstName
            ELSE CompanyName
       END CustomerName
       -- Above: This is the line where it gives an error.  
       -- If there is no Company Name then give the Last and First name of the customer.


      ,CASE WHEN ISNULL(CompanyName, '') = '' 
            THEN ''
            ELSE Cust_FirstName + ' ' + Cust_LastName
       END Attn_To
      -- Above: If there IS a Company Name then give the First and Last name of the customer.

      ,[Address]

FROM CustomerAccount

错误讯息：

  

无法解决SELECT语句中第3列的排序规则冲突。

我尝试了什么：

  ,CASE WHEN ISNULL(CompanyName, '') = '' 
        THEN ''  --Cust_LastName + ', ' + Cust_FirstName
        ELSE CompanyName
   END CustomerName
 -- This works but only gives a CompanyName when there is one.
 -- But does not give me the customer name when there is no CompanyName

如果我只尝试,ISNULL(Cust_LastName, '') + ', ' + ISNULL(Cust_FirstName, '')而不是CASE声明，那么它可以正常工作。我得到了客户的LastName，FirstName。

Answer 1

以下是我修复它的方法：

  ,CASE WHEN ISNULL(CompanyName, '') = '' 
        THEN Cust_LastName + ', ' + Cust_FirstName
        ELSE CompanyName
   END COLLATE Latin1_General_CI_AI CustomerName 

感谢@Aaron Bertrand，@ Paul和@DT。