In have a table in SQL Server defined by
CREATE TABLE [dbo].[ReportDataV2](
[ID] [int] IDENTITY(1,1) NOT NULL,
[DataTypeName] [nvarchar](max) NULL,
[IsInplaceReport] [bit] NOT NULL,
[PredefinedReportTypeName] [nvarchar](max) NULL,
[Content] [varbinary](max) NULL,
[DisplayName] [nvarchar](max) NULL,
[ParametersObjectTypeName] [nvarchar](max) NULL,
CONSTRAINT [PK_dbo.ReportDataV2] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
which happens to be the Dev Express XAF Report table.
In my data context I have
public DbSet<ReportDataV2> ReportDataV2 { get; set; }
I want to be able to treat the DataTypeName field as a discriminator column without interfering with the way ReportDataV2 already works in my code.
I tried the following, but Entity Framework detects that the data structure has changed, and if I generate the migration I see that it is trying to recreate the ReportDataV2 table.
public class OrderCountReport2Configuration : EntityTypeConfiguration<ReportDataV2>
{
public OrderCountReportConfiguration()
: base()
{
ToTable("ReportDataV2", "dbo");
HasKey(tp => tp.ID);
Map<OrderCountReport>(m => m.Requires("DataTypeName").HasValue("OrderCountReport"));
}
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Configurations.Add(new OrderCountReportConfiguration());
base.OnModelCreating(modelBuilder);
}
}
