I started implementing an extension to send the proper data to the web service. The object dimension is start_area, but I am struggling to find how to define the expression to have my data properly formatted.
I think I have to use the aggr function 3 times in my expression, to make 3 nested groups, first by grouping by start_area, then for every start_area group by destination_area, then for every destination_area group by transport_type, then for every distinct (start_area, destination_area, transport_type) tuple evaluate the "sum(amount)" expression.
Is it the right way to do it?
Is it possible to simulate a multi-dimensional objects by nesting aggr?
Re: nested aggr to simulate a multi-dimensional chart
Thanks for your answer Gysbert. However my requirement is to avoid pre-calculations in the load script, in order to be able to update the map by doing selection in the qlikview document, while your solution always give the same result without relation to the current selection state.
Is there a way to dynamically generate the properly formatted input to feed my webservice?
I can achieve what I want with an extension which has start_area, destination_area and transport_type as dimensions, and manually aggregate the data rows in the extension code to create the formatted output, but I also need to get another expression to be evaluated for every start_area so I cannot use a multi-dimensional object.