Entity Framework Code First migration issues -- Dataloss - asp.net-mvc

Question

I've read every blog-post and MSDN articles(http://msdn.microsoft.com/en-us/data/jj591621.aspx) on code first migration but I am little unclear how I should use it.
Here is the Migration history on my project:
Initially I use Enable-Migrations, then Add-Migration and Update-Database.
I deployed the project
I made some minor changes to the model. rerun add-migration and update-database.
deployed the project
I added more attributes to the mode. Also, I run Disable-Migrations and run Enable-Migrations -EnableAutomaticMigration
Now when I deploy the project.. and run the app for the first time, all the existing data is gone
Old Project (step #4) -- Migrations\Configurations.cs
namespace POC_Manager.Migrations
{
using System;
using System.Data.Entity;
using System.Data.Entity.Migrations;
using System.Linq;
internal sealed class Configuration : DbMigrationsConfiguration<POC_Manager.Models.POC_ManagerContext>
{
public Configuration()
{
AutomaticMigrationsEnabled = true;
ContextKey = "POC_Manager.Models.POC_ManagerContext";
}
protected override void Seed(POC_Manager.Models.POC_ManagerContext context)
{
// This method will be called after migrating to the latest version.
// You can use the DbSet<T>.AddOrUpdate() helper extension method
// to avoid creating duplicate seed data. E.g.
//
// context.People.AddOrUpdate(
// p => p.FullName,
// new Person { FullName = "Andrew Peters" },
// new Person { FullName = "Brice Lambson" },
// new Person { FullName = "Rowan Miller" }
// );
//
}
}
}
New Project (step #6) -- Migrations\Configurations.cs
namespace POC_Manager.Migrations
{
using System;
using System.Data.Entity;
using System.Data.Entity.Migrations;
using System.Linq;
internal sealed class Configuration : DbMigrationsConfiguration<POC_Manager.Models.POC_ManagerContext>
{
public Configuration()
{
AutomaticMigrationsEnabled = true;
ContextKey = "POC_Manager.Models.POC_ManagerContext";
}
protected override void Seed(POC_Manager.Models.POC_ManagerContext context)
{
// This method will be called after migrating to the latest version.
// You can use the DbSet<T>.AddOrUpdate() helper extension method
// to avoid creating duplicate seed data. E.g.
//
// context.People.AddOrUpdate(
// p => p.FullName,
// new Person { FullName = "Andrew Peters" },
// new Person { FullName = "Brice Lambson" },
// new Person { FullName = "Rowan Miller" }
// );
//
}
}
}
Old Project (step #4) -- Output from Get-Migrations
PM> Get-Migrations
Retrieving migrations that have been applied to the target database.
201405271907443_AutomaticMigration
201404252210039_InitialCreate
New Project (step #6) -- Output from Get-Migrations
PM> Get-Migrations
Retrieving migrations that have been applied to the target database.
201407022020263_AutomaticMigration
201406262227296_AutomaticMigration
201405271907443_AutomaticMigration
201404252210039_InitialCreate
PM>
Another confusing part is that... Do I still need to run the Update-Database command after enabling automatic migrations ??

Answer 1

Automatic Migrations are for automatically generating migration files based on changes to your classes; you will still need to run Update-Database unless you build logic for it into an initialization strategy.
As far as your data loss, it's most likely based on the initialization strategy that you used. I would suggest that you stick with CreateDatabaseIfNotExists unless your project really needs a custom initializer; the other standard ones are not terribly useful outside of an (early) development environment.