cross apply in sql with sum - sql-server

Question

I have the following query:
insert into [MyDB].[dbo].[Reports_ActivityStat] (ActivityID,TaskID,LS_HowOthersAnswered,LS_ImproveMyChances)
(
SELECT
ActivityID=tasks.ActivityID,
TaskID=tasks.ID,
CAST(
CASE
WHEN CHARINDEX('stats',item.value('(UsedLifeSavers)[1]', 'NVARCHAR(MAX)'))>0
THEN 1
ELSE 0
END AS bit) as LS_HowOthersAnswered,
CAST(
CASE
WHEN CHARINDEX('FiftyFifty',item.value('(UsedLifeSavers)[1]', 'NVARCHAR(MAX)'))>0
THEN 1
ELSE 0
END AS bit) as LS_ImproveMyChances
FROM [MyDB].[dbo].[Tasks] as tasks CROSS APPLY [Progress].nodes ('//Progress/Steps/ProgressStep') Progress(item)
)
which acts on the following Tasks table:
ID | ActivityID | Progress
1 | 1 | [example below..]
2 | 1 | [example below..]
Where Progress is an xml of the sort:
<Progress xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
<Steps>
<ProgressStep>
<FinishedOn>2012-10-30T13:07:52.6374861+02:00</FinishedOn>
<Score>0</Score>
<StartedOn>2012-10-30T13:07:45.8234861+02:00</StartedOn>
<Status>Finished</Status>
<StepIndex>0</StepIndex>
<StepType>Summary</StepType>
<UsedLifeSavers xmlns:a="http://schemas.datacontract.org/2004/07/MindLab.Logic.Study" />
</ProgressStep>
<ProgressStep>
<FinishedOn i:nil="true" />
<PartNumber>1</PartNumber>
<Score>0</Score>
<StartedOn>2012-10-30T13:07:52.6374861+02:00</StartedOn>
<Status>NotFinished</Status>
<StepIndex>1</StepIndex>
<StepType>Information</StepType>
<SubmittedAnswersCount>0</SubmittedAnswersCount>
<UsedLifeSavers xmlns:a="http://schemas.datacontract.org/2004/07/MindLab.Logic.Study">
<a:LifeSavers>Stats</a:LifeSavers>
<a:LifeSavers>FiftyFifty</a:LifeSavers>
</UsedLifeSavers>
</ProgressStep>
</Steps>
</Progress>
(usually there are many more than 2 steps..)
My query yields (not actual data, just sample):
ID | ActivityID | TaskID | LS_HowOthersAnswered | LS_ImproveMyChances
1 | 1 | 1 | 0 | 0
2 | 1 | 1 | 1 | 0
3 | 1 | 1 | 0 | 0
This is almost what I need but not quite.
I need for every unique TaskID the SUM of all LS_HowOthersAnswered and LS_ImproveMyChances.
I was trying to group by, but couldn't make it because it's just too different from regular inner join in that matter..

Answer 1

Found out:
insert into [MyDB].[dbo].[Reports_ActivityStat] (ActivityID,TaskID,LS_HowOthersAnswered,LS_ImproveMyChances)
(
SELECT
ActivityID=tasks.ActivityID,
TaskID=tasks.ID,
SUM (CAST(
CASE
WHEN CHARINDEX('stats',item.value('(UsedLifeSavers)[1]', 'NVARCHAR(MAX)'))>0
THEN 1
ELSE 0
END AS int)
),
SUM (CAST(
CASE
WHEN CHARINDEX('FiftyFifty',item.value('(UsedLifeSavers)[1]', 'NVARCHAR(MAX)'))>0
THEN 1
ELSE 0
END AS int)
)
FROM [MyDB].[dbo].[Tasks] as tasks CROSS APPLY [Progress].nodes ('//Progress/Steps/ProgressStep') Progress(item)
group by tasks.ID
)