SQL Server: Left outer join on whether ID exists - sql-server

Question

The first three items from table ProviderValueCard add their respective amount if = 1. I'm also trying to add 50 to my TotalScore if the ProviderID exists in table SubscriptionsTV. GroupID is also from SubscriptionsTV in which the condition needs to be met. I beleive I need to have a left outer join in the 2nd query on ProviderID columns from both tables.
DECLARE #ProviderID int = '1717';
WITH cte as(
SELECT TOP 1 ProviderID, Time_Stamp,
SUM(CASE WHEN [AdditionalReports] = '1' THEN 5 ELSE 0 END) as AdditionalReports,
SUM(CASE WHEN [UniqueReportRequests] = '1' THEN 15 ELSE 0 END) as UniqueReportsRequests,
SUM(CASE WHEN [SurveyCompleted] = '1' THEN 30 ELSE 0 END) as SurveyCompleted
--IF #ProviderID EXISTS SUM(THEN 50 ELSE 0 END)
FROM ProviderValueCard
WHERE ProviderID = #ProviderID
GROUP BY Time_Stamp, ProviderID
ORDER BY Time_Stamp DESC
)
SELECT ProviderID, Time_Stamp, (AdditionalReports + UniqueReportsRequests + SurveyCompleted) AS TotalScore
FROM cte
--WHERE GroupID = 2
returns
ProviderID Time_Stamp TotalScore
----------- ----------------------- -----------
1717 2014-08-28 13:03:30.593 45
ProviderValueCard table
ProviderID AdditionalReports UniqueReportRequests SurveyCompleted Time_Stamp
----------- ----------------- -------------------- --------------- -----------------------
1717 0 1 1 2014-08-28 13:03:30.593
SubscriptionsTV table
ProviderID GroupID
----------- -----------
1717 2
My final result is this:
DECLARE #ProviderID int = '1717';
WITH cte as(
SELECT TOP 1 a.ProviderID, Time_Stamp,
SUM(CASE WHEN [AdditionalReports] = '1' THEN 5 ELSE 0 END) as AdditionalReports,
SUM(CASE WHEN [UniqueReportRequests] = '1' THEN 15 ELSE 0 END) as UniqueReportsRequests,
SUM(CASE WHEN [SurveyCompleted] = '1' THEN 30 ELSE 0 END) as SurveyCompleted,
MAX(CASE WHEN b.ProviderID IS NULL THEN 0 ELSE 50 END) as SubscriptionExists
FROM ProviderValueCard a
LEFT JOIN SubscriptionsTV b
ON a.ProviderID = b.ProviderID
WHERE a.ProviderID = #ProviderID AND GroupID = 2
GROUP BY Time_Stamp, a.ProviderID, event
ORDER BY event DESC, Time_Stamp DESC
)
SELECT ProviderID, Time_Stamp, (AdditionalReports + UniqueReportsRequests + SurveyCompleted + SubscriptionExists) AS TotalScore
FROM cte

Answer 1

You are correct that this can be accomplished with a LEFT JOIN, and I'd use MAX() with a CASE statement:
DECLARE #ProviderID int = '1717';
WITH Subs AS (SELECT DISTINCT ProviderID
FROM SubscriptionsTV
)
,cte AS (SELECT TOP 1 a.ProviderID, Time_Stamp,
SUM(CASE WHEN [AdditionalReports] = '1' THEN 5 ELSE 0 END) as AdditionalReports,
SUM(CASE WHEN [UniqueReportRequests] = '1' THEN 15 ELSE 0 END) as UniqueReportsRequests,
SUM(CASE WHEN [SurveyCompleted] = '1' THEN 30 ELSE 0 END) as SurveyCompleted,
MAX(CASE WHEN b.ProviderID IS NULL THEN 0 ELSE 50 END) as SubscriptionExists
FROM ProviderValueCard a
LEFT JOIN Subs b
ON a.ProviderID = b.ProviderID
WHERE a.ProviderID = #ProviderID
GROUP BY Time_Stamp, ProviderID
ORDER BY Time_Stamp DESC
)
SELECT ProviderID, Time_Stamp, (AdditionalReports + UniqueReportsRequests + SurveyCompleted + SubscriptionExists) AS TotalScore
FROM cte
Update: Since multiple providerID's can exist, need DISTINCT, used a 2nd cte above, could also use a correlated sub-select inside the CASE statement.
Wasn't paying attention, ORDER BY is fine in a cte when TOP is used.