在INNER JOIN SQL Server上获取DISTINCT记录

Question

我有两个桌子。我有一个通过INNER JOIN子句将第一个表连接到第二个表的查询。结果表明存在冗余或重复的结果。在下面的示例中，结果有4条记录。我想区分SdiID，由于sdiID只有两个唯一的记录，因此我希望只得到两个记录。我尝试在选择之后添加DISTINCT sdiID，但仍然得到4条记录。请帮忙。这是我的查询。

    DECLARE @PageNumber AS INT, @RowspPage AS INT 
        SET @PageNumber = 1 
        SET @RowspPage = 20 
        SELECT totalCount = COUNT(*) OVER(), mailbox.ID as mailboxID, 
          sdi.ID as sdiID
           FROM [SDI].dbo.UserDocumentLocationOutbox mailbox 
           INNER JOIN [SDI].dbo.SDITransaction
           sdi on mailbox.SDITransactionID=sdi.ID 
         INNER JOIN [SYSDB].dbo.DocumentType doc on sdi.DocumentTypeID=doc.ID 
    where mailbox.CommunityID = '9ff10c7a-37f5-4580-9163-6ada55194ca7' 
    and mailbox.UserProfileID = 'f9791614-8cc0-42e3-87d1-53709bc1e099' 
    and doc.CommunityID = '9ff10c7a-37f5-4580-9163-6ada55194ca7' 
    and doc.Active=1 and doc.HideInMailbox=0  
    order by sdi.ProcessedDateTime desc 
OFFSET ((@PageNumber - 1) * @RowspPage) ROWS FETCH NEXT @RowspPage ROWS ONLY

这是结果

Answer 1

  with cte as (SELECT ROW_NUMBER() over(PARTITION BY sdi.ID order by sdi.ID) as rn,totalCount = COUNT(*) OVER(), mailbox.ID as mailboxID, 
          sdi.ID as sdiID
           FROM [SDI].dbo.UserDocumentLocationOutbox mailbox 
           INNER JOIN [SDI].dbo.SDITransaction
           sdi on mailbox.SDITransactionID=sdi.ID 
         INNER JOIN [SYSDB].dbo.DocumentType doc on sdi.DocumentTypeID=doc.ID 
    where mailbox.CommunityID = '9ff10c7a-37f5-4580-9163-6ada55194ca7' 
    and mailbox.UserProfileID = 'f9791614-8cc0-42e3-87d1-53709bc1e099' 
    and doc.CommunityID = '9ff10c7a-37f5-4580-9163-6ada55194ca7' 
    and doc.Active=1 and doc.HideInMailbox=0  
    order by sdi.ProcessedDateTime desc 
OFFSET ((@PageNumber - 1) * @RowspPage) ROWS FETCH NEXT @RowspPage ROWS ONLY)
select totalCount, mailboxID, sdiID
from cte 
where rn < 2

Answer 2

由于您有4个不同的mailboxID值，因此您将始终获得4个查询结果。即，您的每个sdiID都有两个关联的MailboxID，因此它们是不同的记录。您可以通过选择MAX（mailbox.id）作为mailboxID或MIN（Mailbox.id）作为mailboxID并按ID分组来删除每个ID中的一个。