Select data from first date following a specific date (two tables joined) - sql-server

Question

I've searched but can't seem to get this exactly where I need it. This is in regards to Microsoft SQL Server.
I'm looking to join two tables, but only pull in data from the second table for the first date following the date in the first table. See code below.
I've got a table that shows emails sent to customers that looks like this:
SELECT
e.Name
,se.SubscriberID
,se.SendID
,c1.Id
,ds.Service_Num
,sub.EmailAddress
,se.EventDate as 'SentDate'
into #temp_billing_emails
FROM
bi_views.dbo.sfdcMC_SentEvent se
left join bi_views.dbo.sfdcmc_job j on j.jobid=se.sendid
left join bi_views.dbo.sfdcMC_Email e on e.id=j.emailid
left join bi_views.dbo.sfdcMC_Subscriber sub on sub.id=se.SubscriberID
left join sfdcprod.dbo.contact c1 on sub.subscriberkey=c1.id
left join bi_views.dbo.DIM_SERVICE_RF ds on c1.id=ds.ContractSignerContactID_bk
WHERE
e.name like '%Past Due%'
From there, I want to see how many days it took the email receiver to make their first payment following the received email. That's where I've got this:
SELECT
e.*
,z.zuora__createddate__c
,z.zuora__status__c
,z.zuora__amount__c
,datediff(dd,e.sentdate,z.Zuora__CreatedDate__c) DaysToPay
FROM
#temp_billing_emails e
left join sfdcprod.dbo.Service__C sc on e.Service_Num = right(sc.name,len(sc.name)-2)
left join sfdcprod.dbo.[zuora__customeraccount__c] a on sc.billing_account__c=a.id
left join sfdcprod.dbo.[zuora__payment__c] z on a.id=z.zuora__billingaccount__c
WHERE
datediff(dd,e.sentdate,z.Zuora__CreatedDate__c)>=0
and z.zuora__status__c not like 'Error'
That gets me all payments the customer has made after they received an email. What I need is just their first payment amount and the days it took following the email.
I tried the MIN() function like this:
SELECT TOP 100
e.EmailAddress
,e.SentDate
,e.Service_Num
,z.zuora__createddate__c
,z.zuora__status__c
,z.zuora__amount__c
,datediff(dd,e.sentdate,min(z.Zuora__CreatedDate__c)) DaysToPay
FROM
#temp_billing_emails e
left join sfdcprod.dbo.Service__C sc on e.Service_Num = right(sc.name,len(sc.name)-2)
left join sfdcprod.dbo.[zuora__customeraccount__c] a on sc.billing_account__c=a.id
left join sfdcprod.dbo.[zuora__payment__c] z on a.id=z.zuora__billingaccount__c
WHERE
datediff(dd,e.sentdate,z.Zuora__CreatedDate__c)>=0
and z.zuora__status__c not like 'Error'
GROUP BY
e.EmailAddress
,e.SentDate
,e.Service_Num
,z.zuora__createddate__c
,z.zuora__status__c
,z.zuora__amount__c
Any help would be GREATLY appreciated.

Answer 1

outer apply() is a good solution for this type of problem.
select e.*
, x.*
, DaysToPay = datediff(day,e.sentdate,x.Zuora__CreatedDate__c)
from #temp_billing_emails e
outer apply (
select top 1
z.zuora__createddate__c
, z.zuora__status__c
, z.zuora__amount__c
from sfdcprod.dbo.Service__C sc
inner join sfdcprod.dbo.[zuora__customeraccount__c] a
on sc.billing_account__c=a.id
and ds.Service_Num = right(sc.name,len(sc.name)-2)
inner join sfdcprod.dbo.[zuora__payment__c] z
on a.id=z.zuora__billingaccount__c
and z.zuora__status__c not like 'Error'
and z.Zuora__CreatedDate__c >= se.EventDate
order by z.Zuora__CreatedDate__c asc
) as x
I think this is how it would look without the temp table:
select
e.Name
, se.SubscriberID
, se.SendID
, c1.Id
, ds.Service_Num
, sub.EmailAddress
, se.EventDate as 'SentDate'
, x.zuora__createddate__c
, x.zuora__status__c
, x.zuora__amount__c
, DaysToPay = datediff(day,se.EventDate,x.Zuora__CreatedDate__c)
from bi_views.dbo.sfdcMC_SentEvent se
inner join bi_views.dbo.sfdcmc_job j on j.jobid=se.sendid
inner join bi_views.dbo.sfdcMC_Email e on e.id=j.emailid and e.name like '%Past Due%'
left join bi_views.dbo.sfdcMC_Subscriber sub on sub.id=se.SubscriberID
left join sfdcprod.dbo.contact c1 on sub.subscriberkey=c1.id
left join bi_views.dbo.DIM_SERVICE_RF ds on c1.id=ds.ContractSignerContactID_bk
outer apply (
select top 1
z.zuora__createddate__c
, z.zuora__status__c
, z.zuora__amount__c
from sfdcprod.dbo.Service__C sc
inner join sfdcprod.dbo.[zuora__customeraccount__c] a
on sc.billing_account__c=a.id
and ds.Service_Num = right(sc.name,len(sc.name)-2)
inner join sfdcprod.dbo.[zuora__payment__c] z
on a.id=z.zuora__billingaccount__c
and z.zuora__status__c not like 'Error'
and z.Zuora__CreatedDate__c >= se.EventDate
order by z.Zuora__CreatedDate__c asc
) as x