This will be difficult to do by expressions in query because of the inconsistent structure - not every value has height.
I would use VBA procedure to extract the parts and save them into new fields in table. Something like:
Code:
Sub GetDims()
Dim rs As DAO.Recordset
Set rs = CurrentDb.OpenRecordset("SELECT SUPDS1, Length, Width, Height FROM table1;")
Dim aData As Variant, i As Integer
While Not rs.EOF
rs.Edit
aData = Split(rs!SUPDS1, "x")
For i = 0 To UBound(aData)
If InStr(aData(i), "/") Then
rs.Fields(i + 1) = Trim(Left(aData(i), InStrRev(aData(i), "/") + 2))
Else
rs.Fields(i + 1) = Val(aData(i))
End If
Next
rs.Update
rs.MoveNext
Wend
End Sub
Do you have to import this data regularly?