How do I obtain/insert dummy zero week and costs in between valid data - sql

Question

This query is a long shot and has been driving me crazy.
What I want to do is basically insert zero weeks and costs in between the valid weeks and costs in a temp table. See the list below
Practice ID Practice Name Cost Week
1 1 - Practice 1 56.00 18
1 1 - Practice 1 80.00 18
1 1 - Practice 1 122.00 18
1 1 - Practice 1 -80.00 19
1 1 - Practice 1 80.00 19
1 1 - Practice 1 80.00 21
3 3 - Practice 3 80.00 24
3 3 - Practice 3 18.00 28
3 3 - Practice 3 50.00 29
3 3 - Practice 3 18.00 30
3 3 - Practice 3 18.00 34
3 3 - Practice 3 18.00 35
4 4 - Practice 4 36.00 29
4 4 - Practice 4 299.81 31
4 4 - Practice 4 54.00 32
4 4 - Practice 4 132.00 34
4 4 - Practice 4 314.00 35
4 4 - Practice 4 18.00 35
4 4 - Practice 4 501.00 36
4 4 - Practice 4 342.00 36
7 7 - Practice 7 28.00 24
7 7 - Practice 7 56.00 27
7 7 - Practice 7 40.00 27
What I want to do is where there are weeks missing between 1 and 36 for each practice I need to somehow insert zeroed weeks and costs for example
Practice ID Practice Name Cost Week
1 1 - Practice 1 0.00 12
1 1 - Practice 1 0.00 13
1 1 - Practice 1 0.00 14
1 1 - Practice 1 0.00 15
1 1 - Practice 1 0.00 16
1 1 - Practice 1 0.00 17
1 1 - Practice 1 56.00 18
1 1 - Practice 1 80.00 18
1 1 - Practice 1 122.00 18
1 1 - Practice 1 -80.00 19
1 1 - Practice 1 80.00 19
1 1 - Practice 1 80.00 21
As you can see this might seem easy enough but I'm obtaining the payments above from a number of joins the actual week is from a Time table where the date time from the payment is joined to the date time for the week number. Then where there is a matching payment it returns the payment with the payment date.
I've included a depersonalised version of the Query below.
If there is no payment in the payment table then a week number cannot be returned as there is nothing to join it to. (Hard to explain) I have tried to create a temp table with just the fiscal week numbers then update those where there is a payment, but because there is no fixed number of payments per practice per week I cannot determine how many week entries I would need.
If anyone can help with this they're a life saver as this has been giving me a headache for a day or so now.
SELECT R.[Practice id]
,W.[Practice Short Name]
,convert(VARCHAR(10), R.[Practice id]) + ' - ' + W.[Practice Short Name] AS PracticeNumberName
,SUM(R.[Cost]) AS 'Cost'
,I.FiscalWeek
,I.WeekEndingDate
,R.[Owner]
,R.[Description]
FROM dbo.Payments R
INNER JOIN dbo.Time I ON convert(VARCHAR(10), R.[AllocationDate], 121) = convert(VARCHAR(10), I.CalendarDate, 121)
INNER JOIN dbo.OtherDetails W ON R.[Practice id] = W.[Practice Id]
WHERE [paymenttype] NOT IN (5,14,15)
AND I.[FiscalYear] in (2013,2014)
AND I.[FiscalWeek] between 1 and 36
AND R.[cost] <> 0
AND R.[Practice id] IN (1,2,3,4,5,6,7,8,9,10,11,12)
GROUP BY R.[Practice id]
,W.[Practice Short Name]
,convert(VARCHAR(10), R.[Practice id]) + ' - ' + W.[Practice Short Name]
,I.FiscalWeek
,I.WeekEndingDate
,R.[Owner]
,R.[Description]
HAVING sum(R.[cost]) <> 0

Answer 1

Something like this will get you started. You can look after the details.
select i.FiscalWeek, isnull(somefield, 0) cost
, etc
from time i left join payments r on etc
left join other tables
This will give you all the fiscal weeks whether there are matching records in the other tables or not.