Question

I’ve got to design a query in visual studio where I have 2 data sets.

basically it goes like this.

I want to compare this weeks call total to last week per country calling.
the only thing is last weeks calls may have come from 20 diff countries while this weeks might only have come from 15.
How can I make the query such that the 20 countries will show up for both while having “0” value in for countries that do not appear this week.

below is my query:

Select country, 
        Sum(Case When actstatus in (5,105) Then 1 Else 0 End) As TotalCalls,
        Sum(Case When actstatus = 105 Then 1 Else 0 End) As FailedCalls
From  termactivity(nolock)  
    INNER JOIN termconfig(NOLOCK) ON cfgterminalID = actterminalID 
    INNER JOIN Country (nolock) on country = cycode

Where  actstatus in (5,105)
and  (actTerminalDateTime BETWEEN @StartDate-7 AND @EndDate-7)

Group By country
order By country asc

When Act status = 105 it means the call was not completed and when it = 5 it means the call was successful. I am doing this to get a successful call % rate per week.
Thanks in Advance!

Answer 1

From what I understand, you want to perform separate queries for two weeks, and you want both queries to produce rows for all countries, regardless of whether all countries had any calls. To achieve this, you need to use LEFT OUTER JOINS. The below code should guarantee that every country found in the Country table has a row, even if both sums are 0.

SELECT country, 
    SUM(CASE WHEN actstatus IN (5,105) THEN 1 ELSE 0 END) AS TotalCalls,
    SUM(CASE WHEN actstatus = 105 THEN 1 ELSE 0 END) AS FailedCalls
FROM Country (NOLOCK)
    LEFT OUTER JOIN termconfig (NOLOCK) ON country = cycode
    LEFT OUTER JOIN termactivity (NOLOCK) ON cfgterminalID = actterminalID 
WHERE (actTerminalDateTime BETWEEN @StartDate-7 AND @EndDate-7)

GROUP BY country
ORDER BY country ASC

If this was not what you wanted, perhaps you need to clarify your question. Many others have assumed that you want to combine the results into a single query.