Step by step document on Dashboard selectors with BEX as datasource
I am brand new to Xcelsius/Dashboard. I understand that Dashboard is not in SAP's future strategy anymore. However, I want to compare the functionality between Dashboard and Designer Studio.
Can you please point me to any step by step article on using BEX(BICS connection) as datasource while selectors are involved? Most article I found are excel spreadsheet based datasource. However, I am really confused when trying to link the selector with a BEX query.
Thanks in advance,