-- Concatenation refers to the operation of joining two or more strings together into a single string. -- This is commonly used to combine data from different columns or to format strings for output. ...
-- cast(SUM(DATEDIFF(SECOND, DepartureBest, ArrivalBest)) / 3600 as varchar), ':', -- concat('0' , cast((SUM(DATEDIFF(SECOND, DepartureBest, ArrivalBest)) % 3600 / 60 ...