c# - Sql-server 2005 中的内部连接问题

Question

   Select FileUpload.FileName AS FINAME, FileUpload.FilePath,MemberPersonalInformation.FirstName As SharedBy  from FileUpload 
   INNER JOIN 
   ContentManagement ON ContentManagement.FileId=FileUpload.FileId  
   INNER JOIN 
   MemberPersonalInformation ON MemberPersonalInformation.MemberId=ContentManagement.CreatedBy 
   INNER JOIN
    SubjectMaster ON ContentToIndividual.SubjectId=SubjectMaster.SubjectId 
    where 
   FileUpload.FileId in
    (Select FileId from ContentManagement where ContentId in
    (Select ContentId from ContentToIndividual where ShowToMemberId=12) 
    AND ContentManagement.ContentTypeId=1 and ContentManagement.SessionId=4)

当我执行此查询时，在最后一个 JOIN 中出现错误，提示 The multi-part identifier "ContentToIndividual.SubjectId"could not be bound. 但我确实有 SubjectId在两个表中。我不明白问题出在哪里。请帮帮我。

Answer 1

您正在将 SubjectMaster 表连接到您之前未引用过的 ContentToIndividual 表。

在您的 SubjectMaster 加入中引用它之前，您需要加入 contentToIndvidual。

例如

 Select FileUpload.FileName AS FINAME, 
        FileUpload.FilePath,MemberPersonalInformation.FirstName As SharedBy  
from FileUpload 
   INNER JOIN 
   ContentManagement ON ContentManagement.FileId=FileUpload.FileId  
   INNER JOIN 
   MemberPersonalInformation ON MemberPersonalInformation.MemberId=ContentManagement.CreatedBy 
    -- You need to add it in here   
    Inner Join ContentToIndividual on SomeColumn = AnotherColumn
   INNER JOIN
    SubjectMaster ON ContentToIndividual.SubjectId=SubjectMaster.SubjectId 
    where 
   FileUpload.FileId in
    (Select FileId from ContentManagement where ContentId in
    (Select ContentId from ContentToIndividual where ShowToMemberId=12) 
    AND ContentManagement.ContentTypeId=1 and ContentManagement.SessionId=4)

注意:即使您在子查询中查询 ContentToIndividual，如果它不是主选择查询的一部分，您也不能引用其中的列。