Question

我有一个经典ASP页面，可让用户搜索属性和结果页面，然后通过电子邮件发送具有匹配属性的属性代理，让他们知道有租户对其属性感兴趣。

某些代理商可能拥有1个以上的房产，在这种情况下，代理商只需要收到1封电子邮件，而不是每封房产的电子邮件。目前我的代码正在执行后者，我需要它只向每个代理发送一封电子邮件。

在下面的代码中，我有2个记录集; rspropertyresults显示所有匹配的属性，然后我有rsemailagents用于收集代理的电子邮件地址并向他们发送电子邮件。

我想知道是否有人能够看到我如何修改rsemailagents的sql查询以便为每个代理发送1封电子邮件？

<%
[...]
rsemailagents.Source = "SELECT *"
rsemailagents.Source = rsemailagents.Source& "FROM    ("
rsemailagents.Source = rsemailagents.Source& "        SELECT  ContentID"
rsemailagents.Source = rsemailagents.Source& "        FROM    ("
rsemailagents.Source = rsemailagents.Source& "                SELECT  ContentID"
rsemailagents.Source = rsemailagents.Source& "                FROM    VWTenantPropertiesResults"
rsemailagents.Source = rsemailagents.Source& "                WHERE   ContentStreet = '" & Replace(rsemailagents__varReqStreet, "'", "''") & "'"
rsemailagents.Source = rsemailagents.Source& "                UNION ALL"
rsemailagents.Source = rsemailagents.Source& "                SELECT  ContentID"
rsemailagents.Source = rsemailagents.Source& "                FROM    VWTenantPropertiesResults"
rsemailagents.Source = rsemailagents.Source& "                WHERE   ContentTown = '" & Replace(rsemailagents__varReqTown, "'", "''") & "'"
rsemailagents.Source = rsemailagents.Source& "                UNION ALL"
rsemailagents.Source = rsemailagents.Source& "                SELECT  ContentID"
rsemailagents.Source = rsemailagents.Source& "                FROM    VWTenantPropertiesResults"
rsemailagents.Source = rsemailagents.Source& "                WHERE   ContentTrimmedPostCode LIKE '" & Replace(varPostcode, "'", "''") & "%'"
rsemailagents.Source = rsemailagents.Source& "                ) qi"
rsemailagents.Source = rsemailagents.Source& "        GROUP BY"
rsemailagents.Source = rsemailagents.Source& "                ContentID"
rsemailagents.Source = rsemailagents.Source& "        HAVING  COUNT(*) >= 2"
rsemailagents.Source = rsemailagents.Source& "        ) q "
rsemailagents.Source = rsemailagents.Source& "JOIN    VWTenantPropertiesResults r "
rsemailagents.Source = rsemailagents.Source& "ON      r.ContentID = q.ContentID "
rsemailagents.Source = rsemailagents.Source& "WHERE   ContentBedrooms BETWEEN " & Replace(rsemailagents__varBedroomsNoMin, "'", "''") & " "
rsemailagents.Source = rsemailagents.Source& "AND     " & Replace(rsemailagents__varBedroomsNoMax, "'", "''") & " "
rsemailagents.Source = rsemailagents.Source& "AND     ContentPrice BETWEEN " & Replace(rsemailagents__varPriceMin, "'", "''") & " "
rsemailagents.Source = rsemailagents.Source& "AND     " & Replace(rsemailagents__varPriceMax, "'", "''") & " " & varSQL & " "
rsemailagents.Source = rsemailagents.Source& "ORDER BY"
rsemailagents.Source = rsemailagents.Source& "        ContentPrice " & Replace(rsemailagents__varSortWay, "'", "''") & " "
rsemailagents.Source = rsemailagents.Source& "GROUP BY CustomerEmail"

[...]
%>

在我的电子邮件代码中，我将objMail.To设置如下;

objMail.To = (rsemailagents.Fields.Item("CustomerEmail").Value)

这是VWTenantPropertiesResults代码;

SELECT     dbo.VWResidentialLettings.ContentID, dbo.VWResidentialLettings.ContentTitle, dbo.VWResidentialLettings.ContentBriefText, 
                      dbo.VWResidentialLettings.ContentDetails, dbo.VWResidentialLettings.ContentHouseNo, dbo.VWResidentialLettings.ContentStreet, 
                      dbo.VWResidentialLettings.ContentStreet2, dbo.VWResidentialLettings.ContentTown, dbo.VWResidentialLettings.ContentArea, 
                      dbo.VWResidentialLettings.ContentCounty, dbo.VWResidentialLettings.ContentPostCode, dbo.VWResidentialLettings.ContentReference, 
                      dbo.VWResidentialLettings.ContentPrice, dbo.VWResidentialLettings.ContentPricePeriod, dbo.VWResidentialLettings.ContentPriceText, 
                      dbo.VWResidentialLettings.ContentPropertyType, dbo.VWResidentialLettings.PropertyTypeTitle, dbo.VWResidentialLettings.ContentPropertyListType, 
                      dbo.VWResidentialLettings.PropertyListTypeTitle, dbo.VWResidentialLettings.PricePeriodTitle, dbo.VWResidentialLettings.BedRoomNoTitle, 
                      dbo.VWResidentialLettings.ContentBedRooms, dbo.VWResidentialLettings.ContentFurnishing, dbo.VWResidentialLettings.FurnishTypeTitle, 
                      dbo.VWPropertyAgentsActiveSubscriptions.CustomerID, dbo.VWPropertyAgentsActiveSubscriptions.CustomerName, 
                      dbo.VWPropertyAgentsActiveSubscriptions.CustomerBusiness, dbo.VWPropertyAgentsActiveSubscriptions.CustomerAddress1, 
                      dbo.VWPropertyAgentsActiveSubscriptions.CustomerAddress2, dbo.VWPropertyAgentsActiveSubscriptions.CustomerCity, 
                      dbo.VWPropertyAgentsActiveSubscriptions.CustomerArea, dbo.VWPropertyAgentsActiveSubscriptions.CustomerRegion, 
                      dbo.VWPropertyAgentsActiveSubscriptions.CustomerPostalCode, dbo.VWPropertyAgentsActiveSubscriptions.CustomerPhone, 
                      dbo.VWPropertyAgentsActiveSubscriptions.CustomerFax, dbo.VWPropertyAgentsActiveSubscriptions.CustomerURL, 
                      dbo.VWPropertyAgentsActiveSubscriptions.CustomerEmail, dbo.VWResidentialLettings.CountyTitle, dbo.VWResidentialLettings.ContentCreated, 
                      dbo.VWResidentialLettings.ContentUpdated, dbo.VWResidentialLettings.ContentStatus, dbo.VWPropertyImagesList.DocumentFile, 
                      dbo.VWPropertyImagesList.DocumentTitle, dbo.VWResidentialLettings.ContentTrimmedPostCode, dbo.VWPropertyImagesList.ContentStatusTitle
FROM         dbo.VWResidentialLettings INNER JOIN
                      dbo.VWPropertyAgentsActiveSubscriptions ON 
                      dbo.VWResidentialLettings.ContentParentID = dbo.VWPropertyAgentsActiveSubscriptions.CustomerID LEFT OUTER JOIN
                      dbo.VWPropertyImagesList ON dbo.VWResidentialLettings.ContentID = dbo.VWPropertyImagesList.ContentID
WHERE     (dbo.VWResidentialLettings.ContentStatus = 2)

当我在数据库中运行此查询时，它只返回一个CustomerEmail列而不是其他内容;

SELECT DISTINCT CustomerEmail
FROM    (
    SELECT  ContentID
    FROM    (
                SELECT  ContentID
                FROM    VWTenantPropertiesResults
                WHERE   ContentStreet = 'Hull'
                UNION ALL
                SELECT  ContentID
                FROM    VWTenantPropertiesResults
                WHERE   ContentTown = ''
                UNION ALL
                SELECT  ContentID
                FROM    VWTenantPropertiesResults
                WHERE   ContentTrimmedPostCode LIKE 'HU7'
                ) qi
        GROUP BY
                ContentID
        HAVING  COUNT(*) >= 2
        ) q
JOIN    VWTenantPropertiesResults r
ON      r.ContentID = q.ContentID
WHERE   ContentBedrooms BETWEEN 1 AND 10 AND ContentPrice BETWEEN 1 AND 10

Answer 1

将您的查询放入此查询的IN子句

SELECT  email
FROM    agents
WHERE   id IN
        (
        SELECT  agentID
        FROM    …
        )

这将仅选择每个代理一次。

Answer 2

好的...

尝试创建一个子查询，将所有属性组合在一行中。

您可以通过查询创建一个组来完成此操作：

select 
    contentID , count(*) hits 
from 
    VWTenantPropertiesResults 
where 
    propertyValue in ('A','B','C')
group by 
    contentID

此外，您很容易受到SQL注入攻击，因为您在没有正确转义SQL的情况下创建了SQL。在这里考虑参数化查询或存储过程。

您还有一种非常复杂的创建查询的方法。您可以在10多个步骤中构建一个字符串，并将其分配给该属性。考虑在这里使用stringbuilder，因为字符串是不可变的，这可能会导致性能问题（特别是在循环中使用这样的东西时...如果你需要超过5个concats，那么考虑使用stringbuilder）

Answer 3

您有别名'q'的子查询有一个字段ContentID。除非你有非常奇怪的命名约定，否则这不是电子邮件地址。因此，您告诉它“选择CustomerEmail From（没有名为CustomerEmail的字段的类似表的对象）”。这不可能奏效，我很惊讶它返回的不是错误消息。

尝试查看“IN”子句或“EXISTS”子句。

发送电子邮件至DISTINCT电子邮件

3 个答案: