Question

此方案发生在复杂的Silverlight RIA LOB应用程序中我们正在从

升级应用程序

EntityFramework 4 ==> EntityFramework 6
Silverlight RIA ==> Open RIA
Silverlight 4 ==> Silverlight 5
EF Database First ==> EF Code First

我们有一个Code First EF6 Context类，如下所示

public DbContext()
     : base("DefaultConnection")
{
   ...
   public DbSet<Parameter> Parameters{ get; set; }
   public DbSet<ParameterType> ParameterTypes { get; set; }
}


[Table("Parameters")]
public  partial class Parameter
{
    [Key]
    public int ParameterId {get;set;}

    [InverseProperty("ParameterType")]
    public int ParameterTypeId {get;set;}

    [ForeignKey("ParameterTypeId")]
    public virtual ParameterType ParameterType { get; set; }

    public int? StoreId {get;set;}

      ...

}

[Table("ParameterTypes")]
public partial class ParameterType 
{
    [Key]
    public global::System.Int32 ParameterTypeId {get;set;}

    public global::System.String ParameterName {get;set;}

    ...

}

所有东西都会编译并运行良好，直到它发出声明

var t = Context.Parameters.ToList();

异常状态

＆＃34;无效的列名称＆＃39; Discriminator＆＃39;。＆＃34;

表字段都没有名称＆＃34; Discriminator＆＃34; 当我查看生成的SQL Query时，它显示

{SELECT 
 CASE WHEN ([Extent1].[Discriminator] = N'Parameter') THEN '0X' WHEN     ([Extent1].[Discriminator] = N'ImportParameters') THEN '0X0X' WHEN ([Extent1].[Discriminator] = N'RecalcParameters') THEN '0X0X0X' WHEN ([Extent1].[Discriminator] = N'RolloverParameters') THEN '0X0X1X' WHEN ([Extent1].[Discriminator] = N'MassChangeParameters') THEN '0X1X' ELSE '0X2X' END AS [C1], 
    [Extent1].[ParameterId] AS [ParameterId], 
    [Extent1].[ParameterTypeId] AS [ParameterTypeId], 
    [Extent1].[StoreId] AS [StoreId], 
    [Extent1].[FiscalYear] AS [FiscalYear], 
    [Extent1].[ParameterEffectiveDate] AS [ParameterEffectiveDate], 
    [Extent1].[ParameterValue] AS [ParameterValue], 
    [Extent1].[UpdatedOn] AS [UpdatedOn], 
    [Extent1].[UpdatedBy] AS [UpdatedBy], 
CASE WHEN ([Extent1].[Discriminator] = N'Parameter') THEN CAST(NULL AS varchar(1)) WHEN ([Extent1].[Discriminator] = N'ImportParameters') THEN [Extent1].[Prompt] WHEN ([Extent1].[Discriminator] = N'RecalcParameters') THEN [Extent1].[Prompt] WHEN ([Extent1].[Discriminator] = N'RolloverParameters') THEN [Extent1].[Prompt] WHEN ([Extent1].[Discriminator] = N'MassChangeParameters') THEN CAST(NULL AS varchar(1)) END AS [C2], 

    ...

我不知道Discriminator来自哪里，但另一方面，为什么它会对N'RecalcParameters' N'RolloverParameters'之类的字符串进行检查，等等。

经过进一步调查，我意识到我的参数类有另一个部分声明，如

[KnownType(typeof(ImportParameters))]
[KnownType(typeof(RolloverParameters))]
[KnownType(typeof(RecalcParameters))]
[KnownType(typeof(MassChangeParameters))]
[KnownType(typeof(ReforecastParameters))]
public partial class Parameter
{
    ...
}

它有助于解决Silverlight客户端上的复杂实体继承问题。我的狂野猜测是以某种方式＆＃34; KnownType＆＃34;属性以某种方式影响SQL Server脚本生成器。我在互联网上搜索过，无法找到任何可以帮我解决这个问题的线索。

Answer 1

使用此：

    public class DbContext: DbContext
{
   public DbContext()
   {
      Configuration.ProxyCreationEnabled = false;
   }
}

Silverlight RIA EF6 Code First SQL脚本生成未知的Discriminator字段

1 个答案: