The TopCategory Query
Here is the TopCategory query. Add it to Cinema.FilmOpens in a new tab.
Query TopCategory(P1 As %Library.String) As %Library.SQLQuery(CONTAINID = 1)
{
SELECT TOP 3 ID, Description, Length, Rating, Title, Category->CategoryName
FROM Film
WHERE (PlayingNow = 1) AND (Category = :P1)
ORDER BY TicketsSold DESC
}