Entity Framework Automatic Migrations Existing Database

Question

I am building an ASP.Net MVC4 web application with Entity Framework 5. I had to use an existing sql server database but also wanted to use Code First, so I followed this tut

Answer 1

Folks

The answer to my problem above was helped by this article http://christesene.com/entity-framework-4-3-code-first-with-automatic-migrations/

I had to delete my previous initial migration class, and re-create it.

Answer 2

if your context is mine: added a new entity class worked on it but, when I tried to migrate it shows this error, try removing that object from db context then run update-database and add that object again and rerun update-database

for example:

public DbSet<CustomizedEmail> CustomizedEmail { get; set; }
public DbSet<KeyWordsForEmail> KeyWordsForEmail { get; set; }
public DbSet<Notice> Notice { get; set; }//remove it>run update-database>
//add again the above entity and rerurn update-database

this works whether you have data or not. in this process you will loose data in that table.

Answer 3

I had a similar problem.

The cause for me was that the same migration had been run already in the database but under a different MigrationID. I had 201504302005411_InitialCreate but my migration script was called 201505041911076_InitialCreate.

I fixed the issue by renaming the MigrationID in the database to match the one in my code.

I don't quite know how I ended up in the situation but renaming the MigrationID meant the app knew the script had already been run.