Константин Цветков

[Tours]
    [HotelID]         INT            NOT NULL
    [CityID]          INT            NOT NULL,
    [CountryID]       INT            NOT NULL,

SELECT Hotels.[Name] AS HotelName, 
       Cities.[Name] AS CityName, 
       Countrys.[Name] AS CounrtyName,
       (SELECT MIN(Price)
          FROM HotelsRooms
          WHERE (HotelID = Hotels.ID)) AS MinPrice, 
        Hotels.Rating AS Stars, 
        Hotels.Line, 
        Hotels.DistanceToBeach, 
        Hotels.DistanceToAirport
  FROM Hotels 
    INNER JOIN Cities ON Hotels.City = Cities.ID 
    INNER JOIN Countrys ON Cities.CountryID = Countrys.ID
  WHERE ((@toCity IS NULL) OR (Cities.[Name] = @toCity)) 
    AND ((@toCountry IS NULL) OR (Countrys.[Name] = @toCountry))

SELECT MIN(Price) FROM HotelsRooms WHERE (HotelID = 14)

SELECT        (SELECT        MIN(Price) AS Expr1
                          FROM            HotelsRooms
                          WHERE        (HotelID = 14)) AS Expr1
FROM            Hotels
WHERE        (Id = 14)

SELECT        (SELECT        MIN(Price) AS Expr1
                          FROM            HotelsRooms
                          WHERE        (HotelID = Hotels.Id)) AS MinPrice
FROM            Hotels
WHERE        (Id = 14)