First, I would check if the analytic function you are using is supported by the underlying data source. If yes, check the execution trace to see if it is correctly delegated.
You can check the list of supported functions in Denodo in the user manual.
* [Analytic Functions](https://community.denodo.com/docs/html/browse/latest/vdp/vql/appendix/syntax_of_condition_functions/analytic_functions_window_functions)
Hope this helps!