How do I build a MDX query that considers only facts that happened in the last 10 days of February? - mdx

Question

I have a fact table that has a time dimension, which contains year, month, day and hour.
I was able to find ways to filter things that happened in a given day, or month (simple where/filter by the desired level). But I would like to create an MDX query that filter the results so my cube has information about the facts recorded in the last 10 days of febraury.
Is there anyway I can do it?

Answer 1

Assuming you have all the days of February in your cube, you could use a set inside there WHERE clause.
Something like this..
WHERE ([Date].Month)
Supposing you have a Year-Month-Day-Hour hierarchy in place and there may be some dates missing
Select....... on COLUMN,
....... ON ROWS
FROM ....
WHERE
({[Time].[Month].&[Feb 2015].LastChild.LAG(10) : [Date].[Month].&[Feb 2015].LastChild})
If no dates are missing in the date dim,
select ... ON COLUMNS,
... ON ROWS
FROM ...
WHERE
({[Time].[Date].&[02/19/2015] : [Date].[Date].&[02/28/2015]})
If you want the sales for last 10 days of Feb for every year:
SELECT Measures.Sales ON COLUMNS,
Products.Products.MEMBERS ON ROWS
FROM
(
SELECT
generate //This would build the set for the last 10 days of Feb for every year
(
[Time].[Year].[All].children,
TAIL //This returns the last 10 days of february(second month)
(
[Time].[Year].CURRENTMEMBER.FIRSTCHILD.LEAD(1).CHILDREN,
10
)
) ON COLUMNS
FROM YourCube
)

Answer 2

Just as some extra info - if you want a "rolling" 10 day sum or 10 day average then code similar to the following is a possible approach:
WITH
MEMBER [Measures].[Sum 10] AS
Sum
(
LastPeriods
(10
,[Date].[Calendar].CurrentMember
)
,[Measures].[Internet Order Count]
)
MEMBER [Measures].[MovAvg 10] AS
Avg
(
LastPeriods
(10
,[Date].[Date].CurrentMember
)
,[Measures].[Internet Order Count]
), format_string = "#.000"
SELECT
{
[Measures].[Internet Order Count]
,[Measures].[Sum 10]
,[Measures].[MovAvg 10]
} ON 0
,Descendants
(
[Date].[Calendar].[Month].&[2006]&[2]
,[Date].[Calendar].[Date]
) ON 1
FROM [Adventure Works];
It returns data like the following: