Linq 查询导致无效的列名 SqlException

Question

ASPNET MVC5 网络应用，Visual Studio 2015

网站是语言本地化的，所以我需要根据文化参数获取本地化的类别。

category_trans 表用于提供类别名称翻译，而ISO_Languages 用于接收文化代码参数并将其相关 id 传递给category_trans。

型号：

public partial class Product
{
    public int? ID { get; set; }
    public string Name { get; set; }
    public string Description { get; set; }
    public int CategoryID { get; set; }
    public virtual category_trans category_trans { get; set; }
}

public partial class Category
{
    public int ID { get; set; }
    public string Name { get; set; }
    public int? ParentID { get; set; }
    public bool IsDeleted { get; set; }
}

public class category_trans
{
    [Key]
    [Column(Order = 1)]
    public int category_id { get; set; }
    [Key]
    [Column(Order = 2)]
    public int language_id { get; set; }
    public string name { get; set; }
}

public class ISO_Languages
{
    public int ID { get; set; }
    public string code { get; set; }
    public bool IsEnabled { get; set; }
    public string name_en { get; set; }
    public string name_fr { get; set; }
    public string name_it { get; set; }
    public string name_de { get; set; }
    public string name_es { get; set; }
}

public static IQueryable<Product> ActiveProductsPerUser(BaseContext db, string userid, string culture)
    {
        return from p in db.Products
               from ct in db.category_trans
               from l in db.ISO_Languages
               where (ct.category_id == p.CategoryID
               && ct.language_id == l.ID
               && l.code.Substring(0, 2) == culture)
               select p;
    }

导致错误：

System.Data.SqlClient.SqlException：列名“category_trans_category_id”无效。列名“category_trans_language_id”无效。在 System.Data.SqlClient.SqlCommand.c.b__174_0(Task1 result)
in System.Threading.Tasks.ContinuationResultTaskFromResultTask2.InnerInvoke()
在 System.Threading.Tasks.Task.Execute()

另请注意，我将预期结果传递给另一种排序和分页方法，因此接受IQueryable 作为输入（没有IEnumerable）。

Answer 1

试试这个；

public static IQueryable<Product> ActiveProductsPerUser(BaseContext db, string userid, string culture)
    {
        var query = (from p in db.Products
                     join ct in db.category_trans
                     on p.CategoryID equals ct.category_id
                     join l in db.ISO_Languages
                     on ct.language_id equals l.ID
                     where l.code.Substring(0, 2) == culture)
                     select p).ToList();

        return query;
    }