Deploying entity framework code first with production database

c# database entity-framework mysql sql-server

Question

I've developed a pretty simple web app using entity framework code first. I realized after hours of frustration that even though localdb is SQL Server Express it is actually not meant to be used with production when using 'publish' (the publish wizard). FYI I'm using EF 6.1.3, SQL Server 2014, VS 2013, and IIS 7.

If I understand correctly, when you click publish with localdb, all you're really doing is copying your localdb database to your IIS 7 server. I couldn't figure out why that when I updated my lodaldb database through VS migrations that my production server database wasn't being updated. I understand (and believe now) that it's actually two different instances of localdb, and hence not the same data.

OK whatever - I'm done with localdb and I created a real SQL Server 2014 db on my machine. I've googled for hours and can't figure out what to do now. I have some questions:

  1. How do I manage this new database using EF? For instance, suppose I want to add a new column. First I add it to my localdb, do some testing, and do the migration using Add-Migration blah then Update-Database... Do I then have to generate a SQL script using VS and then manually run that on the production DB server?

  2. I know this isn't great, but instead of using local DB with entity framework, can I just attach EF to a real staging SQL Server database (a test one) and skip all this localdb bull****? Then could I manage it using code-first migrations and keep everything in sync?

  3. Am I supposed to use an Initializer? I've read conflicting reports about whether to use these or not for a production db (like this one)

    public class PricedNotesInitializer: MigrateDatabaseToLatestVersion<...,...> { }

It's frustrating that the only way I learn about this stuff is through blog posts from other people frustrated. I don't understand why the documentation is so garbage.

Thanks for your help and sorry for the rant.

1
10
9/15/2016 2:06:06 PM

Accepted Answer

If you work on SQL express edition locally then you can migrate it pretty easily to the SQL production server.SQL production server can be a SQL Azure or your own production server.

A 1. You just need to change your local connection string to a production one and run below command on package manager. Then all your not updated migration scripts will run on the production.

PM> Update-Database

A 2 : I don't recommend this method.

A 3 : You can do that like this :

 Database.SetInitializer(new CreateDatabaseIfNotExists<YourDbContext>());
1
9/15/2016 2:17:00 PM

Popular Answer

Using an initializer

You can use the MigrateDatabaseToLatestVersion initializer so schema changes to the database will be (if possible without data loss) done automatically when your application first starts up after a deploy.

If data loss would occur you'll get an error and have to take appropriate action. This can be overriden to proceed even with data loss.

Development environment setup experience

As other answers already pointed out, you need one connection string per environment so the LocalDB is fine for development, I would even encourage it because it can be created and initialized (and seeded with test data) automatically for any new developer that needs to develop or debug it just by building and running the application from source.

The "set up new development environment" experience should be as smooth as possible with as few and preferably zero manual steps apart from loading the solution, building and running the code-base.

Automate your release cycle

Your deploy and release pipeline should be automatic and not require any manual commands that might be executed wrongly, be forgotten or worse.

What could be a manual step is a simple yes/no approval on the staged changes if you want to be careful or fulfill some compliance requirements.

Automated tests in your staging environment should however alleviate this and when successful automatically deploy to production - in a perfect world ;)

Running update-database manually against production requires that whatever machine is running it has access to the production database - an unlikely or not-recommended scenario if you're running it interactively I would say. If required you could script it as part of your automated deploy pipeline if you want more control over it than using the initializer, which seems best suited for simpler projects (which this one seemed to be though).



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