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Question

有任何 Access 大师可以帮助我吗？试图弄清楚如何实现以下目标：我想要一个查询遍历个人表中的每个人，并返回那些在圣诞节列表字段中具有真实值的人。该数据库很旧，并且是使用 CompanyName 作为公司表的主键创建的（我知道 - 设计不佳）。为了让一家公司拥有多个地点，他们创建了一个地址栏字段。这样，如果“Y 公司”在圣地亚哥开设新位置，他们会添加“Y 公司 - 圣地亚哥”条目并在地址行中输入“Y 公司”。然后对于没有公司的个人，将他们输入到“Home”的虚拟公司条目中。所以理想情况下，我希望这个查询做的是循环，抓住所有应该在圣诞节名单上的人，如果地址栏字段 ISN'T NULL 我希望 CompanyName 等于 AddressLine，但如果 CompanyName = " Home" 我希望 CompanyName 等于 ""（空字符串）。还有一些人有隔夜地址，因为他们的正常地址是邮政信箱。以下查询我主要为我工作，但是如果 CompanyName="Home"，我不清楚如何在返回的结果中将公司名称设为空白。

SELECT tblIndividuals.FirstName, tblIndividuals.LastName, IIf([tblcompanies].[addressline] Is Not Null,[tblcompanies].[addressline],[tblcompanies].[companyname]) AS CompanyName, IIf([tblIndividuals].[MailingAddress1] Is Null,[tblCompanies].[MailingAddress1],[tblIndividuals].[MailingAddress1]) AS MailingAddress1, IIf([tblIndividuals].[MailingAddress1] Is Null,[tblCompanies].[MailingAddress2],[tblIndividuals].[MailingAddress2]) AS MailingAddress2, IIf([tblIndividuals].[MailingAddress1] Is Null,[tblCompanies].[MailingAddress3],[tblIndividuals].[MailingAddress3]) AS MailingAddress3, IIf([tblIndividuals].[MailingAddress1] Is Null,[tblCompanies].[MailingAddress4],[tblIndividuals].[MailingAddress4]) AS MailingAddress4, IIf([tblIndividuals].[MailingAddress1] Is Null,[tblCompanies].[City],[tblIndividuals].[City]) AS City, IIf([tblIndividuals].[MailingAddress1] Is Null,[tblCompanies].[State],[tblIndividuals].[State]) AS State, IIf([tblIndividuals].[MailingAddress1] Is Null,[tblCompanies].[Zip],[tblIndividuals].[Zip]) AS Zip
FROM tblIndividuals INNER JOIN tblCompanies ON tblIndividuals.CompanyName = tblCompanies.CompanyName
WHERE (((tblIndividuals.ChristmasList)=True))
Order by [tblIndividuals].[companyname];

如果可能的话，我希望它按公司名称值 (A-Z) 排序，然后按个人的姓氏 (A-Z) 排序。我不会假装精通 SQL，所以您能给我的任何帮助将不胜感激。感谢您的时间。

Answer 1

考虑一个 UNION 查询，例如：

SELECT i.FirstName, i.LastName, 
       IIf(c.[addressline] Is Not Null,
           c.[addressline],c.[companyname]) AS CompanyName, 
       c.[MailingAddress1] AS MailingAddress1, 
       c.[MailingAddress2] AS MailingAddress2, 
       c.[MailingAddress3] AS MailingAddress3, 
       c.[MailingAddress4] AS MailingAddress4, 
       c.[City] AS City, 
       c.[State] AS State,
       c.[Zip] AS Zip
FROM tblIndividuals i
INNER JOIN tblCompanies c ON i.CompanyName = c.CompanyName
WHERE i.ChristmasList=True
AND i.[MailingAddress1] Is Null
UNION
SELECT i.FirstName, i.LastName, 
       IIf(c.[addressline] Is Not Null,c.[addressline],
           c.[companyname]) AS CompanyName, 
       i.[MailingAddress1] AS MailingAddress1, 
       i.[MailingAddress2] AS MailingAddress2, 
       i.[MailingAddress3] AS MailingAddress3, 
       i.[MailingAddress4] AS MailingAddress4, 
       i.[City] AS City, 
       i.[State] AS State,
       i.[Zip] AS Zip
FROM tblIndividuals i
INNER JOIN tblCompanies c ON i.CompanyName = c.CompanyName
WHERE i.ChristmasList=True
AND i.[MailingAddress1] Is Not Null

您可以将查询括在括号中以创建一个派生表，您可以使用查询设计窗口对其进行排序。

SELECT FirstName, LastName, etc 
FROM ( <union query> ) As q
Order by q.[companyname]