缺少记录

Question

我将视图复制到新表中。但是，视图中存在一些记录，但表中没有。

此外，当我使用SELECT ... NOT IN：

时，我找不到所有丢失的记录

DECLARE @email NVARCHAR(256)='xxx@xxx.com'
SELECT Email FROM dbo.vw_DirectoryData WHERE Email=@email
SELECT Email FROM dbo.tblDirectoryData WHERE Email=@email
SELECT Email FROM dbo.vw_DirectoryData WHERE email NOT IN(SELECT email FROM dbo.tblDirectoryData)

Result:

Email
xxx@xxx.com
(1 row(s) affected)

Email
(0 row(s) affected)

email
(0 row(s) affected)

我尝试了另一个方法：

DECLARE @email NVARCHAR(256)='xxx@xxx.com'
SELECT     vw_DirectoryData.Email, tblDirectoryData.Email AS [Email in Table]
FROM         vw_DirectoryData LEFT OUTER JOIN
                      tblDirectoryData ON vw_DirectoryData.Email = tblDirectoryData.Email WHERE vw_DirectoryData.Email=@email

SELECT     vw_DirectoryData.Email, tblDirectoryData.Email AS [Email in Table]
FROM         vw_DirectoryData LEFT OUTER JOIN
                      tblDirectoryData ON vw_DirectoryData.Email = tblDirectoryData.Email WHERE tblDirectoryData.Email IS null

    Result:

    Email
Email in Table

    xxx@xxx.com
NULL

    (1 row(s) affected)

    Email                                                                                                                                                                                                                                                           Email in Table
    (0 row(s) affected)

任何建议如何克服这个问题？

Answer 1

尝试使用NOT EXISTS：

SELECT viw.Email
FROM dbo.vw_DirectoryData viw 
WHERE NOT EXISTS(SELECT tbl.* FROM dbo.tblDirectoryData tbl WHERE tbl.Email = viw.Email)

Answer 2

您

NOT IN (SELECT email FROM dbo.tblDirectoryData)

如果取出所有NULL，

将起作用。所以添加WHERE子句。

NOT IN (SELECT email FROM dbo.tblDirectoryData WHERE email IS NOT NULL)

将NULL视为＆＃34;未知＆＃34;，所以如果电子邮件未知，则不知道它是否与某些东西相等（可能是......）

Answer 3

我弄清楚了，问题出在数据类型中。我正在从不同的表中读取以创建视图。视图使用UNION ALL组合来自其他3个视图的数据。

我通过创建读取源数据然后将其插入标准表的SSIS包解决了这个问题。然后读取数据并在相同的视图中应用我需要的所有格式和连接。