adding a foreign key with Code First migration

Question

I have an error when trying to update my database after adding a migration.

Here are my classes before add-migration

public class Product
{
    publi         


        

Answer 1

I came across this problem today. Here's how I handled it. I did have to make my FK property nullable which was not a big deal in my case.

I made my changes to my POCO, generated the migration and then added the following to the migration.

public partial class LineItemProductionHistory_v4 : DbMigration
{
    public override void Up()
    {
        AddColumn("LineItemProductionHistories","TempLineItemId",c=>c.Int());
        Sql("Update LineItemProductionHistories Set TempLineItemId = LineItem_Id");
       .
       . Generated code
       .
        Sql("Update LineItemProductionHistories Set LineItemId = TempLineItemId");
        DropColumn("LineItemProductionHistories", "TempLineItemId");
    }
}

I'm just temporarily storing all off the foreign keys, letting the migration do it's add/drop stuff and then putting the foreign keys back in the newly created FK.