Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Tahir Hassan — Wed, 08 Feb 2012 13:02:02 GMT

It is worth putting up a notice at the top of this article that EF 4.3 Beta 1 is released and link to that article:

blogs.msdn.com/.../ef-4-3-beta-1-released.aspx

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Kristoffer Garcia — Wed, 11 Jan 2012 23:45:54 GMT

The Data Motion / Custom SQL bit, specifically the code shown at the end of this comment, is causing a SqlException with the following message "Invalid column name 'Abstract'". I tried generating and running the script for this command and the same thing happens. I've been told that this is standard behavior for SQL Server, so I'm kinda wondering how come it worked for you guys. Is this a configuration issue or a bug in code first migrations?

AddColumn("Posts", "Abstract", c => c.String());

Sql("UPDATE dbo.Posts SET Abstract = LEFT(Content, 100) WHERE Abstract IS NULL");

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Jarrett Vance — Wed, 04 Jan 2012 01:55:01 GMT

I love migrations. You guys are doing a great job.

I want to echo Leandro's question: if you have an existing database with existing data, how do you do the initial migration? It seems like you must wipe the database to get the first migration.

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Leandro Guimarães — Wed, 21 Dec 2011 02:18:52 GMT

I wonder what the ideal way to work with (Migration) when working with a (database) existing.

I'm deleting the (Up and Down) generated by the first (Add-migration) and giving the next update just starting changes.

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Krzysiek S — Thu, 15 Dec 2011 21:14:12 GMT

I didn't know about the DbMigrator class, thanks. I think that I can use this with some DI to get the same functionality. Though I must say that it is a really nice feature in code first that I could just change the config value and not having to worry about anything else

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Andrew J Peters — Thu, 15 Dec 2011 17:45:11 GMT

@Krzysiek S,

If you are using the runtime DbMigrator class to setup your test database, then you could have a separate MigrationsConfiguration with a different Seed method. Otherwise, you could run different seed logic from the one Seed method by examining which database is currently being targetted. Take a look at the properties available on DbMigrationsConfiguration like ConnectionStringName etc.

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Krzysiek S — Thu, 15 Dec 2011 11:34:59 GMT

EF has the initializers that I'm able to configure in .config file and change depending on the environment that the app is run on. Is there anything similar to this in migrations? I'd like to seed the test db with dummy data, but the integration db with only the required stuff

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Guillermo — Wed, 14 Dec 2011 16:44:24 GMT

Hi, i noticed that you can seed the database through migrations, but the way that you guys recomend this, is writting those seeds at the configuration.cs, that works fine but everytime I do Update-Database, those seeds are going to populate my DB, is there is a way that those seeds populate the database only once, maybe implementing the seeds at the migrations or something like that?

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Krzysiek S — Wed, 14 Dec 2011 14:50:10 GMT

I do have one more question - is it possible to use migrations with an existing application? I have an app in version 0.1 in which I haven't used migrations. Now I have a codebase for 0.2 and would like to generate a db diff script...

I know that I can always go to the repo, fetch code for 0.1, generate a migration, fetch code for 0.2, copy the migration over, generate the next migration. But maybe there is a quicker way?

re: Code First Migrations: Beta 1 ‘No-Magic’ Walkthrough

Krzysiek S — Wed, 14 Dec 2011 14:42:11 GMT

Thanks Brice and Rowan.

Great job on the migrations tool - love it so far.