Entity Framework CTP 4 - Code First Custom Database Initializer

Question

I would like to implement a custom database initialization strategy so that I can generate the database schema and apply it to an EXISTING EMPTY SQL database using a supplied User ID and Password.

Unfortunately the built-in strategies don’t provide what I’m looking for:

// The default strategy creates the DB only if it doesn't exist - but it does 
// exist so this does nothing
Database.SetInitializer(new CreateDatabaseOnlyIfNotExists<DataContext>());

// Drops and re-creates the database but then this breaks my security mapping and 
// only works if using a “Trusted" connection
Database.SetInitializer(new RecreateDatabaseIfModelChanges<DataContext>());

// Strategy for always recreating the DB every time the app is run. – no good for 
// what I want
Database.SetInitializer(new AlwaysRecreateDatabase<DataContext>());

I have worked out the following but this does not create the ModelHash so I’m unable to use "context.Database.ModelMatchesDatabase()" to validate that the database schema has been created and prevent multiple initializations:

public class Initializer : IDatabaseInitializer<DataContext>  
{ 
    Public void InitializeDatabase(DataContext context)  
    {       
         // this generates the SQL script from my POCO Classes
         var sql = context.ObjectContext.CreateDatabaseScript();

         // As expected - when run the second time it bombs out here with "there is already an
         // object named xxxxx in the database"
         context.ObjectContext.ExecuteStoreCommand(sql); 

         this.seed(context)
         context.SaveChanges();
    }
}  

Questions:

Does anyone know how I can get/create the model hash? (which is an EdmMetadata Entity)

-Or-

Is there a better way of doing this in general using the Code First CTP?

Answer 1

The Entity Designer Database Generation Power Pack will do this. Not sure if it works with Code First yet, but worth a shot.