.NET Core 3.1 dbset model migration to multiple SQL tables

Question

I'm trying a code first approach to creating multiple logging tables for a data archiver. The data that is being archived conforms to one model, but there are three different databases that the archiver queries data from. So I want to have three different SQL tables, one for each database.

ArchiveDataModel:

 public class ArchiveDataModel
    {
        [Key]
        public int ID { get; set; }
        public string EventId { get; set; }
        public string EventData { get; set; }
        public string DateCreated { get; set; }
        public string DateArchived { get; set; }
    }

Here's my ApplicationDbContext:

public class ApplicationDbContext : DbContext
    {
        public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options) : base(options)
        {

        }

        public DbSet<ArchiveDataModel> EventDataArchive_A { get; set; }
        public DbSet<ArchiveDataModel> EventDataArchive_B { get; set; }
        public DbSet<ArchiveDataModel> EventDataArchive_C { get; set; }
   }

Running "add-migration" here creates a migration package for a table named "ArchiveDataModel." So I added this:

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<ArchiveDataModel>()
            .ToTable("EventDataArchive_A")
            .ToTable("EventDataArchive_B")
            .ToTable("EventDataArchive_C");
        }

But this only creates a migration package for "EventDataArchive_C."

Would it be possible to use this one model to generate three identical tables via code-first approach?

Answer 1

Seems that both Fluent Api and Data Annotations could not solve this issue as far as these instruments target model class, not DbSet.

What you could do is to have a base class, 3 derived classes from a base class and 3 DbSet-s in your context each over corresponding derived model

public abstract class ArchiveDataModel
{
    [Key]
    public int ID { get; set; }
    public string EventId { get; set; }
    public string EventData { get; set; }
    public string DateCreated { get; set; }
    public string DateArchived { get; set; }
}

public class ArchiveDataModel_A : ArchiveDataModel { }
public class ArchiveDataModel_B : ArchiveDataModel { }
public class ArchiveDataModel_C : ArchiveDataModel { }

public class MyDbContext : DbContext
{
    public MyDbContext(DbContextOptions<MyDbContext> options)
        : base(options)
    { }

    public DbSet<ArchiveDataModel_A> EventDataArchive_A { get; set; }
    public DbSet<ArchiveDataModel_B> EventDataArchive_B { get; set; }
    public DbSet<ArchiveDataModel_C> EventDataArchive_C { get; set; }
}