Emit DbContext.OnModelCreating on every context creation

Question

I use entity framework code first to work with my database. I have several tables with different names but same structure, and this tables dynamically appears in database. H

Answer 1

Look like nobody knows answer...

Otherwise, one man told me that my question is meaningless because of storage data in several tables will not give any achievement. More better to add indexes to database, partitioning table or something else. In other words this is Database Management System problem. But if some one knows answer I'll be very pleasured to hear something about EF hack.

Answer 2

There is a built-in feature which may address your issue : `IDbModelCacheKey ; the implementation of which is to be registered in your configuration. The point is to generate a different key for your different contexts.

I would go for something like :

First, the configuration

public class EntityFrameworkConfiguration: DbConfiguration
{
    public EntityFrameworkConfiguration()
    {
        this.SetModelCacheKey(ctx => new EntityModelCacheKey((ctx.GetType().FullName + ctx.Database.Connection.ConnectionString).GetHashCode()));
    }
}

Then the implementation of the IDbModelCacheKey

public class EntityModelCacheKey : IDbModelCacheKey
{
    private readonly int _hashCode;

    public EntityModelCacheKey(int hashCode)
    {
        _hashCode = hashCode;
    }

    public override bool Equals(object other)
    {
        if (other == null) return false;
        return other.GetHashCode() == _hashCode;
    }

    public override int GetHashCode()
    {
        return _hashCode;
    }
}

Finally, your DataContext

public class DataContext : DbContext
{

  string setElementsTableId; 

  // use the setElementsTableId as extended property of the 
  // connection string to generate a custom key
  public DataContext(string setElementsTableId)
        : base(ConfigurationManager.ConnectionStrings["RepositoryConnectionString"] 
 + "; Extended Properties=\"setElementsTableId=" + setElementsTableId + "\"")
  {
    this.setElementsTableId = setElementsTableId;
  }

  public DbSet<Entities.SetElement> SetElements { get; set; } 

  protected override void OnModelCreating(DbModelBuilder modelBuilder)
  {
    if (!string.IsNullOrEmpty(setElementsTableId))
    {
        modelBuilder.Entity<Entities.SetElement>().Map(x => x.ToTable(setElementsTableId)); 
    }
  }
}

I hope this will be of some help