Hello everebody!   Pls i need to your advise.  I need to allows a number of flow-files together into a single flow-file with use general key. For example, i have two flow-files with next attributes: manager_name = John Dow costumer_info = Matt Damon costumer_location = LA   and   manager_name = John Dow costumer_info = Tony Stark costumer_location = LA   Next, I need to recieve single flow-file with count result of the flow-files with general key = John Dow Finally single flow-file whith attributes: manager_name = John Dow total = 2   How i can do it in nifi?   ... View more