Hi !
I have a table which displays products contained in orders for a specified timespan, but as orders contain several lines the order reference (and other redundant information) gets repeated on each matching product row. Is there a way to only show it on the first row ?
You could start by using LEAD/LAG functions for next or previous. Depends upon your database though.
I agree that they can be daunting. I still check the documentation most times I need them.