/* * select sum(f.price) * from flights f, company c * where f.companyName = c.name and c.name = "Lufthansa" */ public double Query6() { return (FlightTable.joinFunc( CompanyTable, t => t.Item1.CompanyName == t.Item2.Name && t.Item2.Name == "Lufthansa").Reduce( 0.0, (s, t) => s += t.Item1.Price)); }
/* * select * * from flights f, airport a * where f.destinationAirport = a.name && f.destinationCity = a.city * */ public IEnumerable <Tuple <Flight, Airport> > Query4() { return (FlightTable.joinFunc (AirportTable, t => t.Item1.DestinationAirport == t.Item2.Name && t.Item1.DestinationCity == t.Item2.City)); }
/* * select f.code, f.company, a.size * from flights f, airport a * where f.destinationAirport = a.name && f.destinationCity = a.city && f.company = Lufthansa * */ public IEnumerable <Tuple <string, string, AirportSize> > Query5() { return (FlightTable.joinFunc( AirportTable, t => t.Item1.DestinationAirport == t.Item2.Name && t.Item1.DestinationCity == t.Item2.City && t.Item1.CompanyName == "Lufthansa").Map( t => new Tuple <string, string, AirportSize>(t.Item1.Code, t.Item1.CompanyName, t.Item2.Size))); }