嵌套查询没有适当的键

Question

首先，我有一个函数，它有两个参数(经度，纬度)。

  RETURNS TABLE 
  AS
  RETURN 
   (
    select dbo.GeoCalculateDistance (@lat1Degrees,@lon1Degrees,Latitude,Longitude) as    Distance, PKRestaurantId as PkKeyId from StRestaurant
   )

如你所知，我有一张桌子叫餐厅。在这个表中，我有4列(PkRestaurantId, RegionId, Longitude, Latitude)。

并且，我需要一个接受4个参数的方法

 public List<RestaurantDetailDto> GetRestaurant(int regionid, decimal latitude, decimal longitude, OrderType orderType)
    {}

这个方法会给我周围的餐馆。但是如果我想用距离系统化这个列表，我必须将我的Restaurant table和函数连接起来。这是我的查询。

            var query = from restaurant in context.StRestaurant
                        join distance in context.CalculateDistanceTable(latitude, longitude) on restaurant.PKRestaurantId equals distance.PkKeyId
                        where restaurant.FKRegionId == regionid 
                        select new
                            {
                                Restaurant = restaurant,
                                DistanceTable = distance,
                            };

然后检查orderType

      switch (orderType)
            {
                case OrderType.Distance:
                    query = query.OrderBy(x => x.DistanceTable.Distance);
                    break;
            // and the anothers
            }

最后，我试着把这个列表作为;

      var queryResult = query.ToList();

我一直在犯这个错误:

嵌套查询没有合适的键

我也尝试了上面的查询，但它返回相同的错误:s

    var query = context.StRestaurant.Where(x => x.FKRegionId == regionid && x.IsActive).Join(
                context.CalculateDistanceTable(latitude, longitude),
                restaurant => restaurant.PKRestaurantId,
                result => result.PkKeyId,
                (restaurant, result) => new
                    {
                        Restaurant = restaurant,
                        MinumumPackagePrice = restaurant.StRestaurantRegionRelation.FirstOrDefault(x => x.FKRestaurantId == restaurant.PKRestaurantId).MinumumPackageCharge,
                        DistanceTable = result,
                        RestaurantImage = restaurant.StRestaurantImage.Where(x => x.IsDefault && x.FKRestaurantId == restaurant.PKRestaurantId),
                    }
                );

请帮助! !

Answer 1

我以前在对结果执行. include()时看到过这种情况。我想象你的投影(在第二个例子中)可能在内部做这个。你能把这个加到第一部分吗?

在本例中，我必须在源表上添加.Include():

from a in context.A.Include("relationship") join b in context.MyFunction(...) ...

Answer 2

您可以在这里尝试一些事情。首先，重写SQL函数，使它有一个主键:

CREATE FUNCTION CalculateDistanceTable 
(
    -- Add the parameters for the function here
    @lat1Degrees float, 
    @lon1Degrees float
)
RETURNS 
@RestaurantDistances TABLE 
(
    -- Add the column definitions for the TABLE variable here
    PkKeyId int NOT NULL primary key, 
    Distance float NOT NULL
)
AS
BEGIN
    INSERT INTO @RestaurantDistances
    SELECT        dbo.GeoCalculateDistance(@lat1Degrees, @lon1Degrees, Latitude, Longitude) AS Distance, PKRestaurantId AS PkKeyId
    FROM            StRestaurant
    RETURN 
END
GO

同样，你可以尝试改变你的LINQ连接，使用匿名类型来执行连接。

var query = from restaurant in context.StRestaurant
            join distance in context.CalculateDistanceTable(latitude, longitude) on new { Key = restaurant.PKRestaurantId } equals new { Key = distance.PkKeyId }
                    where restaurant.FKRegionId == regionid 
                    select new
                        {
                            Restaurant = restaurant,
                            DistanceTable = distance,
                        };

如果这些都没有帮助，请告诉我，我会尽量在适当的时候更新这个答案。