EF backward compatibility DB migration

Question

I am trying to understand how to implement the following deployment scenario using EF code and migration. The idea is that I would like to update the database with backward compatibility changes (for example: add a column) and check that it still works. It is inspired by the introduction of green / blue, but does not fully match this pattern. The rationale for this is the following process:

• Database Update (EF Migration)
• Test Website
• Update Website Code
• If something goes wrong, return to the previous site code

The problem that I will certainly encounter is that in step 2 (and 4) I will definitely get an error from EF about changing the model, although all database changes are compatible with the existing code ...

I know that the solution would be to transfer the Down database to the previous version (or even make a backup copy of the database), but it may happen that some migrations are really complicated, and the Down part may be broken or just poorly encoded.

So my question is: is there a way to avoid EF model validation or, in the end, to know that the changes are backwards compatible?

Answer 1

Setting dbinitializer to null will result in a loss of compatibility check, for example.

public class MyDBContext: DbContext { public MyDBContext() : base("myConnString") { //Disable initializer Database.SetInitializer<MyDBContext>(null); } public DbSet<A> As { get; set; } public DbSet<B> Bs { get; set; } } 

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