In my last post I had an example for a function to return a single value from an MDX query which has certain performance drawbacks when being used in many Excel fields.
Since Excel supports matrix formulas to do a computation on multiple values, this can also be used for MDX query results. Another benefit for this approach is, that dimension members that are added later on, are also displayed in the query result.
Before I post the function code, here's the result. For my test, I used this MDX query on the Adventure Works cube:
SELECT
{
[Measures].[Internet Sales Amount],
[Measures].[Internet Order Quantity],
[Measures].[Internet Gross Profit]
} ON 0,
[Product].[Category].[Category] ON 1
FROM [Adventure Works]
The result, when being called from SQL Server Management Studio, looks like this:
The following screenshot shows how this result looks like in Excel using the matrix MDX formula:
Now, what are the #N/A entries about? The matrix formula measures the size of the resulting cell area and returns a two dimensional array of exactly that size. When entering the formula I chose a larger area on the worksheet in order to be prepared for additional entries on both axes. Of course you could think of returning a larger matrix from the function in order to properly fill out the unused cell. The best approach would be to supply width and height as parameters.
So, this is how the formula is to be entered:
Be sure to press CTRL+ALT+ENTER when entering the formula in order to turn it into a matrix formula.
The MDXGetMDX function takes five parameters:
| Parameter | Description | Example |
| Server | Hostname of the SSAS server | localhost |
| InitalCatalog | Name of the SSAS database | Adventure Works DW |
| Cube | Name of the SSAS cube | Adventure Works |
| mdx | MDX code of the query | select ... on 0, ... on 1 from cubename |
| WithCaption | When true, captions are printed | true |
Finally, here's the code I used for the MDGetMDX(...) function:
Function MDGetMDX(Server As String, InitialCatalog As String, Cube As String, mdx As String, WithCaption As Boolean) As Variant
On Error GoTo errorhandler:
Dim cset As New ADOMD.Cellset
Dim conn As New ADODB.connection
Dim x As Variant
Dim i As Integer, j As Integer
Dim i0 As Integer, j0 As Integer ' begin of the data area
Dim i1 As Integer, j1 As Integer ' size of the data area
conn.Open "Data Source=" & Server & ";Provider=MSOLAP;Initial Catalog=" & CatalogName & "" & InitialCatalog & ""
cset.Open mdx, conn
If cset.Axes.Count > 2 Then
MDGetMDX = "More than 2 axes are not allowed!"
Exit Function
End If
If cset.Axes.Count > 0 Then i1 = cset.Axes(0).Positions.Count Else j1 = 0
If cset.Axes.Count > 1 Then j1 = cset.Axes(1).Positions.Count Else j1 = 0
If WithCaption Then
' column headings are displayed as rows
If cset.Axes.Count > 1 Then i0 = cset.Axes(1).DimensionCount Else i0 = 0
' row headings are displayed as columns
If cset.Axes.Count > 0 Then j0 = cset.Axes(0).DimensionCount Else j0 = 0
Else
i0 = 0
j0 = 0
End If
If cset.Axes.Count = 2 Then
ReDim x(j0 + j1 - 1, i0 + i1 - 1)
ElseIf cset.Axes.Count = 1 Then
ReDim x(j0, i0 + i1 - 1)
Else
ReDim x(1, 1)
End If
For i = 0 To UBound(x, 2)
For j = 0 To UBound(x, 1)
x(j, i) = ""
Next
Next
' Show caption:
If WithCaption Then
For i = 0 To i1 - 1
For j = 0 To cset.Axes(0).Positions(i).Members.Count - 1
x(j, i + i0) = cset.Axes(0).Positions(i).Members(j).Caption
Next
Next
For j = 0 To j1 - 1
For i = 0 To cset.Axes(1).Positions(j).Members.Count - 1
x(j + j0, i) = cset.Axes(1).Positions(j).Members(i).Caption
Next
Next
End If
If cset.Axes.Count = 2 Then
For i = 0 To i1 - 1
For j = 0 To j1 - 1
x(j + j0, i + i0) = nz(cset(i, j).Value, 0)
Next
Next
ElseIf cset.Axes.Count = 1 Then
For i = 0 To i1 - 1
x(j0, i + i0) = nz(cset(i).Value, "")
Next
Else
x(0, 0) = cset(0).Value
End If
MDGetMDX = x
cset.Close
conn.Close
Exit Function
errorhandler:
MDGetMDX = Err.Description
End Function
Function nz(x As Variant, other As Variant) As Variant
If Not IsNull(x) Then
nz = x
Else
nz = other
End If
End Function

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