c# - LinQ 到实体 : Query with four tables JOIN

Question

我有四张 table :

- Client with PK ClientID.
- Destination with PK DestinationID.
- Language with PK LanguageID.
- DestinationDetail with PK DestinationID.
- RL-Client-Destination with PKs ClientID and DestinationID.

客户端可能有零个或n个目的地。一个目的地有 n 个 DestinationDetails，每个 DestinationDetail 都有一种语言。

好的。我需要检索给定客户端和给定语言的所有 DestinationDetails。

我开始写这个:

try
   {
      ObjectQuery clientes = 
          guiaContext.Cliente;
      ObjectQuery destinos =
          guiaContext.Destino;
      ObjectQuery idiomas =
          guiaContext.Idioma;
      ObjectQuery detalles =
          guiaContext.DetalleDestino;

      IQueryable detalleQuery =
          from cliente in clientes
          from destino in destinos
          from idioma in idiomas
          from detalleDestino in detalles
          where destino.
          select detalleDestino;

   }
   catch
   {
   }
}

有什么建议吗？

谢谢!

Answer 1

其大致思路是:

var detalleQuery =
          from client in guiaContext.Clients
          where client.ID == 1
          from destination in cliente.Destinations
          from destinationDetail in destination.DestionationDetails
          where destinationDetail.Language.Iso2Code == "es"
          select destinationDetail;