Question

I use EF Code First in my solution with SQL Server Express behind it. When I update my model, I always have to delete my database before restarting my solution. I know this is because my database is no more up to date. In that case, I lose all data in my tables.

I would like to be able to update my models (for example: adding a new field) and keeping all data in my tables.

Even if I update manually my database, when I restart the solution, I get the error below:

The model backing the ‘EntityFrameworkDbContext’ context has changed since the database was created. Either manually delete/update the database, or call Database.SetInitializer with an IDatabaseInitializer instance

Any suggestions?

Thanks.

Answer 1

You can remove the creation of EdmMetadata table as follows.

public class MyContext : DbContext
{

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Remove<IncludeMetadataConvention>();
    }
}

This way you can manually update the database without getting the error.

You can check out Code First Migrations