Question

我需要在SQL Server 2008中设置一个工作，在本月的第一天运行，向我们的客户发送电子邮件。但是，我不知道如何遍历子查询的结果。

导致此错误消息：

子查询返回的值超过1。这是不允许的子查询跟随=，！=，＆lt;，＆lt; =，＆gt;，＆gt; = 或者子查询用作表达

以下是相关代码：

SET @Recipients =(SELECT DISTINCT a.EMail
         FROM   a
        --approximately 600 email addresses 

SET @MailSubject = 'Customer News' 
SET @MailRecipients = @Recipients
SET @MailMessage =  'Dear customer, Attached is your customer news letter.'

SET @FileName = N'E:file\to\be\attached.doc'

EXEC msdb.dbo.sp_send_dbmail @recipients = @MailRecipients, 
    @body = @MailMessage,
    @blind_copy_recipients='misj@mikl.org', 
    @subject = @MailSubject,
    @file_attachments  = @FileName

Answer 1

错误在于您有许多行尝试分配给单个变量

SET @Recipients =(SELECT DISTINCT a.EMail
     FROM   a
    --approximately 600 email addresses

您需要将其更改为单独的列表

SET @Recipients = STUFF(
           (select DISTINCT ';' + CAST(a.EMail AS varchar(max))
           FROM a FOR XML PATH ('')
           )
          ,1,1, '')

注意：@Recipients需要是varchar（max）

Answer 2

问题是@recipients = @MailRecipients。它期待一个字符串（一个电子邮件地址），你给它一个记录集。

子查询返回的值超过1

2 个答案: