Instruction
Great! Of course, you can partition rows by multiple columns. Take a look:
SELECT RouteId, Ticket.Id, Ticket.Price, SUM(Ticket.Price) OVER(PARTITION BY Journey.RouteId, Journey.Date) AS SumPrice FROM Ticket INNER JOIN Journey ON Ticket.JourneyId = Journey.Id;
We wanted to show each ticket price with the sum of all ticket prices on a particular route on a particular date. Neither of the tables would suffice on its own, so we had to join them together to get all the columns we needed.
Exercise
Show the Id of each journey, the Date on which it took place, the Model of the train that was used, the MaxSpeed of that train and the highest MaxSpeed of any train traveling the same route on the same day (HighestMaxSpeed).
Stuck? Here's a hint!
Use MAX(MaxSpeed) OVER(PARTITION BY RouteId, Date).



