T) When to use sort within groups ?
Use Sort within Groups only if records within a group are processed before being sorted on a minor key. i.e. if processing "A" needs records to be sorted on field {"1"} and later in the flow processing "B" needs records to be sorted on field {"1", "2"}. In this case before processing "2" and after processing "1" use sort within groups with major-key as {"1"} and minor key as {"2"}. If records are not grouped to start with, use Sort with a multi-part key. There is no benefit to using Sort within Groups directly after using a Sort component.