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Currently in QA when I get the error message saying that the database has changed, I simply drop the database in QA.

In production, I don't have access to the database directly from my development machine so I can't run migrations on the production database directly.

What should I do?

Can I disable change tracking on production and simply manually modify the database by adding the new columns etc?

I'm using EF 6.1.1

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In addition to setting the database initializer to null, as per @stevenrcfox, you might also want to look at generating a script to provide to a DBA to update the database. This is often useful in situations where the DBA has review processes they need to go through and needs to see and potentially modify the SQL before executing it.

To achieve this you can generate a script from package manager console, or migrate.exe, that that will move a database between two specific migrations. An example, direct from get-help update-database -detailed:

C:\PS>Update-Database -Script -SourceMigration Second -TargetMigration First # Generate a script to migrate the database from a specified start migration # named "Second" to a specified target migration named "First"

Alternatively, if you don't know what version the production database is currently sitting at, you can generate a mega-script that will take care of upgrading from any version. Again, from the Entity Framework NuGet powershell command help:

C:\PS>Update-Database -Script -SourceMigration $InitialDatabase # Generate a script that can upgrade a database currently at any version to the latest version. # The generated script includes logic to check the __MigrationsHistory table and only apply changes # that haven't been previously applied.

A DBA might not like the results of this last one, though, due to its length and lots of irrelevant script given that the production database is only likely to need the last few migrations.

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DBA can apply migrations from command line, using migrate.exe.

Note, that term "change tracking" means "track changes, made in entities". It isn't related somehow with model/database changes.

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is it possible for me to delete the __migrations table and just do it manually?
Of course this is possible. What approach is preferred for you?
I prefer in production to make manual changes to the database schema (add new columns to tables etc) but when I do that EF should ignore the __migrations table. Possible?
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You can set the Database Initialiser to null, this is I'm assuming what you meant by 'disable change tracking'

This can be achieved by doing the following:

Database.SetInitializer<context>(null);

Your initialiser is most likely set to MigrateDatabaseToLatestVersion (possibly in the web.config)

Not using migrations on production is probably the safest, your application may not have permissions to edit table structures in production anyway!

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If I don't disable, will it run migrations automatically? Or do you have to manually run migrate.exe or something?
IIRC not by default, you can set it to automatically update, by extending MigrateDatabaseToLatestVersion & setting AutomaticMigrationsEnabled to true in the constructor (not recommended for production!)

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