MDX Range with non existing members - ssas

Question

I have a MDX query where the string is parsed from a front-end application with forms. End users can restrict a query based on a free text field where they can input a range from invoice number and to invoice number. The query gets build based on this 2 parameters:
SELECT
{[Measures].[Amount]} ON COLUMNS,
NON EMPTY
(
(
[Invoices].[Invoice Number].[Invoice Number].[100000000]:[Invoices].[Invoice Number].[Invoice Number].[222222222])
) ON ROWS
FROM [MyCube]
However the range operator fails if an end user types in a non existing member. I think that I need to convert these fields somehow to a decimal number and than do the check with > and <.
I already have some ideas. However I am not able to get it to work. Here I try to just filter on numbers > 0 (If this works I can fill the the parameter for > and add one for <.
SELECT
{[Measures].[Amount]} ON COLUMNS,
(
FILTER(
[Invoices].[Invoice Number].[Invoice Number].members
, Cdec([Invoices].[Invoice Number].Currentmember.Properties("Key")) > 0
)
) ON ROWS
FROM [MyCybe]
However after 5 minutes I still have no response.. so cancelled the query.

Answer 1

I've calculated this way (it's for dates, but the idea is the same):
with
member [Measures].[RD_Key] as CDec([Report Date].[Report Date ID].Currentmember.Member_Key)
member [Measures].[ResultFilter] as [RD_Key]>20130801 and [RD_Key]<20131013
select {[Measures].[Count],[Measures].[RD_Key]} on 0
,Filter([Report Date].[Report Date ID].members,[Measures].[ResultFilter]) on 1
FROM [DATA]

Answer 2

If FILTER is slow maybe try using the HAVING clause. I'm assuming that no conversion of the Member_Key is needed as keys are usually numeric:
WITH
MEMBER [Measures].[Inv_Key] as
[Invoices].[Invoice Number].Currentmember.Member_Key
SELECT
{
[Measures].[Amount]
,[Measures].[Inv_Key]
} ON COLUMNS
,[Invoices].[Invoice Number].[Invoice Number].members
HAVING
[Measures].[Inv_Key] > 100000000
AND
[Measures].[Inv_Key] < 222222222
ON ROWS
FROM [DATA]