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Entity Framework Code First with DbUp

I am thinking of using Entity Framework 6 Code First for database interaction alongside DbUp for database schema update. The thing is I don't want to use EF migration for reasons. So, the workflow that I've reached to is:
Change model (add POCOs, alter properties, etc)
Run Add-Migration temp_file in Visual Studio Package Manager Console
Run Update-Database -Script in Visual Studio Package Manager Console
Grab the generated sql scripts including insertion of new row in table __MigrationHistory
Create a new .sql file and past the generated scripts
Delete temp_file
Run DbUp
It works perfectly locally and on production server, however I don't feel comfortable with adding and then deleting temp_file every time a new migration is generated (I wish there were a way to permanently stop temp_file being added to the solution.).
So question:
Is there a better way to do database migration with DbUp using Entity Framework?

In most of the cases you can skip steps (2) and (6) by utilizing the Automatic Code First Migrations:
Automatic Migrations allows you to use Code First Migrations without having a code file in your project for each change you make.
By default automatic migrations are disabled. You enable them by adding the following like in your db migration configuration class constructor (usually called Configuration and located under Migrations sub folder):
AutomaticMigrationsEnabled = true;
Some things to consider:
Documentation states that automatic migrations have limitations, so be aware.
You can mix automatic and code based migrations (in other words, the proposed and your current approaches).
The benefits of your current approach is that you can preview how EF interprets your model changes and also add/remove/change parts of the migration code.
The automatic migrations have been deprecated (don't exist) in EF Core, so in EF Core projects you have to use something similar to your current approach, except that you have to keep the generated migration code files.

Maybe this answer is too late, but maybe it will be useful as well. I completely understand your approach to use Entity Framework as ORM and a different tool for schema migration. But choosing DbUp requires you to write manually SQL or generate them as you described above. I suggest considering to use FluentMigrator instead of DbUp. It follows the same philosophy, but allows writing migration steps in C# using fluent syntax. In addition, it supports downgrades, i.e. rollback.
Here is an example:
[Migration(1)]
public class CreateUserTable : Migration
{
public override void Up()
{
Create.Table("Users");
}
public override void Down()
{
Delete.Table("Users");
}
}

Entity Framework 7: How do I update my database with only a specific migration?

I'm having some issues updating my database to reflect my model changes using migrations in EF7. At first, I create a model (let's just say Person for example), created an initial migration, and updated my database.
dnx ef migrations add Initial
dnx ef database update
No problems there, everything worked fine. However, now I'm creating another model (let's say "Car") that I also want to create a table for. So I followed the same steps: add a new migration, and try updating my database using dnx like below.
dnx ef migrations add CreateCarTable
dnx ef database update CreateCarTable
This is where I get my problems. Even though I'm specifying the specific migration I want to use, it keeps trying to run all of them, so I'm getting an error complaining that tables already exist (in my case it's the AspNetRoles tables that gets created in the "Initial" migration).
Has anyone had similar problems and/or have a solution to this?

How to add missing migrations for Identity? (Invalid object name 'dbo.AspNetRoles')

I have created an asp.net application and on my development machine it created these built in tables which is necessary to use the identity part in asp.net mvc.
However, after the initial create when I had to create an SwitchToIdentityDbContext migration which had all the logic to create these tables. But in my application at the time, these tables did already exist so I removed that logic. After that (I think) it resulted in the missing tables for identity when I try to deploy my application to a new datasource that does not have these tables.
Is there a way to generate the missing migrations in order to get this running?
As of now, I have this in my config:
AutomaticMigrationsEnabled = true;
AutomaticMigrationDataLossAllowed = true;
Even if I remove that migration and add a new one, it's empty.

If you don't care for the data residing in your database, one option to correct the schema is to delete all your .cs migrations in Visual Studio and all records in your dbo.__MigrationHistory table in your database. After that you can try to create a brand new migration in Visual Studio to fix the database.
However if that doesn't work, you can clear all your migrations in Visual Studio and completely obliterate the database. Then run
add-migration CreateMyDb, then update-database
and you should be good to go.
If you do care for your data, you can always export the contents of your database tables to .csv files in Server Management Studio (if you use it) before destroying the migrations.

How to change database after altering model in MVC?

I'm new to ASP.NET and I'm working on this project that uses MVC. It's a simple website development project, and it uses SQL Server CE (.sdf) as the database.
I would like to change a couple of the underlying models, but that causes errors in the database.
I understand that I would need to change the database, and I know it's possible to create models automatically from the database.
I'm wondering if there is any way to create a database from the models. i.e. I don't mind losing all the data, but is there a way for me to change the models and then create a database that supports the existing models.
I hope that makes sense

Yes it possible to
Here is how you can do it.
There are two approaches to accomplish this task.
Method-1. (Via Package Manager Console)
This approach for the Code First.
Open your project and go to Package Manager Console as follows
Tools--> Nuget Package Manager--> Package Manager Console
First Enable Migrations in your project.Type following in console.
enable-migrations -contexttypename yourContextName
This command will add a Migrations folder in your project inside this folder you will
see Configuration.cs inside this file you will see a seed method
protected override void Seed(YourContext context)
you can use this method to seed your database.
Now run following command in your package manager console
add-migration anyNameOfInitialMigrations
Finally To update the database simply run following command.
update-database
Method-2.
Best approach for Model First.
Open your .edmx file.
Right Click--> on the model and then select "Generate Database From Model"
Make Sure you have proper connection strings in your web.config.

The model backing the '--Context' context has changed since the database was created - but db is new production database

I've got this error for the 762nd time but this time I am getting it as soon as I attempt to access my Production site, straight after deleting the 'production' database on Azure and then publishing my site.
The model backing the 'PropertyContext' context has changed since the database was created. Consider using Code First Migrations to update the database
I deleted the database because I couldn't fix this issue any other way but it still doesn't work.
Some important points:
I'm using EF6 and publishing to Azure.
This is 1 of 2 projects/sites that uses the same Repo project. I have no
problems with the other one, just this one.
I have tried publishing the problem project first (after deleting the db) and
second with the same result.
I have tried deleting both WEBSITES and the DB from Azure and starting again
I have tried deleting all migrations and starting with a fresh data model
I have tried the following in my Global.asax (in both projects)
Database.SetInitializer PropertyContext>(null); <-- SO won't let me put the first <
and
Database.SetInitializer(new MigrateDatabaseToLatestVersion<PropertyContext, MyConfiguration>());
new PropertyContext().Database.Initialize(true);
I'm using .net 4.5
Why am I getting this error on a new database and how can I get this site to work?

Just ran into the same error in ASP.Net application. In my case I did not use Code First, but I used standard ASP.Net authentication provider which apparently uses Code First, and authentication was broken because of this issue.
Here is quick and dirty solution is you don't care much about existing user records:
For me the solution was to drop the dbo.__MigrationHistory table, authentication started working fine after that. Be aware! This solution is not for everyone! This will fix the problem, but it is potentially risky.
If you cannot afford to lose data in AspNet* tables:
ASP.Net authentication provider automatically creates tables in your database:
AspNetRoles
AspNetUsers
AspNetUserRoles
AspNetUserClaims
AspNetUserLogings
The tables are empty by default, if you haven't created any new logins for your web site, you can use "quick and dirty" solution above. If you do care about preserving user information or just curios how Code First migrations work, follow these steps:
Open your Web.config file and check the name of the connection string you have for your database. It will be one of the records under <connectionStrings> element.
Open Package Manager Console:
Tools –> Library Package Manager –> Package Manager Console
In Package Manager Console window, use a drop-down to set Default Project. Make sure this is the project that contains ASP.Net authentication provider code.
Execute command:
Update-Database -ConnectionStringName MyConnectionStringName
Replace the MyConnectionStringName with the actual name you looked up in web.config.
As a result of this command you will see a new folder "Migrations" with a bunch of code generated by the Update-Database command. Re-build and re-deploy your app, your new migration code will be executed on startup and would bring the database schema in sync with an updated version of ASP.Net authentication provider code.

When using Code First with Migrations, your database creates a table called __MigrationHistory to track the current schema. When you run your application your Entity Framework will check this table to make sure that the database schema matches your database entities. If they do not match, you will get this error.
To update your database follow these steps:
Open the Package Manager Console (View -> Other Windows -> Package Manager Console) in Visual Studio
In the Package Manager Console Window, there is a drop down with your projects in, make sure it is set to the project that contains your DbContext
Make sure that the project that contains your App.Config / Web.Config file is "Set as Startup Project" (If you have multiple Configs, it must be the one with the Database Connection String defined.
Type Update-Database -ConnectionStringName MyConnString where MyConnString is the name (not the actual connection string) of your connection string in your App.Config / Web.Config
If you get an error like this: "Unable to update database to match the current model because there are pending changes and automatic migration is disabled."
You should enable Automatic Migrations and try again.
To enable Automatic Migrations
In the Migrations folder (in the project with your DbContext), open Configuration.cs.
Make sure the Constructor contains: AutomaticMigrationsEnabled = true;
To stop Entity Framework/DbContext from monitoring changes on your database you could simply delete the __MigrationHistory table in your database. It is then up to you to make sure that the database remains updated manually.
MSDN article here

The solution from this is to use the static method SetInitializer and bind to the context a Null value. If you are working on a Web solution, the best position to write the code is in the Application_Start of your Global.asax.cs file.
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
RegisterRoutes(RouteTable.Routes);
//...
Database.SetInitializer<MyContext>(null);
}

I got a similar problem this morning. Suddenly the error appeared and couldn't be resolved:
The model backing the 'ApplicationDbContext' context has changed since
the database was created. Consider using Code First Migrations to update
the database
I have one project for MVC and another project for the model, context and repositories. I've been working on it for weeks but today it said stop.
I have tried to delete database, enable-migration, add-migration and update-database so many times that I've lost count. I've added initializers to MigrateDatabaseToLatestVersion as well as DropCreateDatabaseIfModelChanges. All in vain...
What finally made it work was to move model, context and repositories into the MVC project (not something I was keen on)...then it worked right out of the box without any code changes at all (besides namespaces)! Very strange...
I've read so many blog posts during the day trying to solve this problem. One of them (I don't know which one) mentioned a bug in Visual Studio 2013 where reference to DLL files weren't always updated as they should, suggesting that my MVC project missed out something when I was running add-migration and update-database in my separate project. But it's just a guess.
I'm using EF 6.1 and .Net 4.5.1 in my solution.

Got a similar problem! Answer is here
http://www.asp.net/mvc/overview/older-versions/getting-started-with-aspnet-mvc3/cs/adding-a-new-field
(Rick Anderson)
There are two approaches to resolving the error:
Have the Entity Framework automatically drop and re-create the database based on the new model class schema. This approach is very convenient when doing active development on a test database, because it allows you to quickly evolve the model and database schema together. The downside, though, is that you lose existing data in the database — so you don't want to use this approach on a production database!
Explicitly modify the schema of the existing database so that it matches the model classes. The advantage of this approach is that you keep your data. You can make this change either manually or by creating a database change script.

I have spent some hours trying to solve this problem. One project was working, the other one wasn't.
I had different projects referencing different versions of Entity Framework. In my case, I had a Console app and a Windows Service app, both referencing a third project containing code first classes and DbContext.
After running Update-Package EntityFramework everything worked fine in both projects.