Updating a code-first database with migrations - entity-framework

Question

I've been through answers on this question here and so far nothing mention applies or has fixed the issue.
Edit
What I've tried:
Updated ContextKey column in __MigrationHistory table.
Copied all my older migrations back from the old version of my project.
Problem
I've just come across an error in my app that was caused by 0 values in a column that's supposed to link 2 tables. As such, I've updated my data model to structure a relationship between them:
public class ContactGroup
{
public int Id { get; set; }
public string Name { get; set; }
}
public class Contact
{
public int Id { get; set; }
public ContactGroup ContactGroup { get; set; }
// other contact columns go here
}
One of the other tables I have is called Campaigns, so now having added a migration that sets up my foreign keys, I want to update-database
Here's where my problem is since I'm getting an error saying:
There is already an object named 'Campaigns' in the database.
I know there's already an object with this name in the database because its one of the objects I'm establishing a relationship to.
Here's the Migration as generated by Entity Framework
public partial class StructuredRelationships : DbMigration
{
public override void Up()
{
CreateTable(
"dbo.Campaigns",
c => new
{
Id = c.Int(nullable: false, identity: true),
Name = c.String(),
Client = c.String(),
EmailAddress = c.String(),
PhoneNumber = c.String(),
FaxNumber = c.String(),
PhysicalAddress = c.String(),
PostalAddress = c.String(),
DateSent = c.DateTime(),
SmtpServerAddress = c.String(),
SmtpServerPort = c.Int(nullable: false),
SmtpServerUser = c.String(),
SmtpServerPassword = c.String(),
Deleted = c.Boolean(nullable: false),
SendInterval = c.Int(nullable: false),
})
.PrimaryKey(t => t.Id);
CreateTable(
"dbo.ContactGroups",
c => new
{
Id = c.Int(nullable: false, identity: true),
Name = c.String(),
Deleted = c.Boolean(nullable: false),
})
.PrimaryKey(t => t.Id);
CreateTable(
"dbo.Contacts",
c => new
{
Id = c.Int(nullable: false, identity: true),
ContactGroupId = c.Int(nullable: false),
CompanyName = c.String(),
Salutation = c.String(),
FirstName = c.String(),
LastName = c.String(),
EmailAddress = c.String(),
Telephone = c.String(),
DirectTel = c.String(),
Mobile = c.String(),
BroadDesignation = c.String(),
Designation = c.String(),
EmployeeCount = c.Int(nullable: false),
EmployeeCountBand = c.String(),
SaTelProvince = c.String(),
SaBroadArea = c.String(),
Town = c.String(),
Suburb = c.String(),
Type = c.String(),
SpecificBusinessClassification = c.String(),
ReferenceNumber = c.String(),
Deleted = c.Boolean(nullable: false),
})
.PrimaryKey(t => t.Id)
.ForeignKey("dbo.ContactGroups", t => t.ContactGroupId, cascadeDelete: true)
.Index(t => t.ContactGroupId);
CreateTable(
"dbo.Emails",
c => new
{
Id = c.Int(nullable: false, identity: true),
CampaignId = c.Int(nullable: false),
TemplateId = c.Int(nullable: false),
Sender = c.String(),
From = c.String(),
FromAddress = c.String(),
ReplyTo = c.String(),
ReplyToAddress = c.String(),
Subject = c.String(),
Body = c.String(),
Footer = c.String(),
DateCreated = c.DateTime(nullable: false),
Deleted = c.Boolean(nullable: false),
})
.PrimaryKey(t => t.Id)
.ForeignKey("dbo.Campaigns", t => t.CampaignId, cascadeDelete: true)
.Index(t => t.CampaignId);
CreateTable(
"dbo.EmailSends",
c => new
{
Id = c.Int(nullable: false, identity: true),
CampaignId = c.Int(nullable: false),
EmailId = c.Int(nullable: false),
ContactGroupId = c.Int(nullable: false),
SendDate = c.DateTime(nullable: false),
TotalRecipients = c.Int(nullable: false),
TotalSent = c.Int(nullable: false),
TotalFailed = c.Int(nullable: false),
Status = c.String(),
CompletedDate = c.DateTime(),
Deleted = c.Boolean(nullable: false),
TrackerUrl = c.String(),
})
.PrimaryKey(t => t.Id)
.ForeignKey("dbo.Campaigns", t => t.CampaignId, cascadeDelete: true)
.ForeignKey("dbo.ContactGroups", t => t.ContactGroupId, cascadeDelete: true)
.ForeignKey("dbo.Emails", t => t.EmailId, cascadeDelete: true)
.Index(t => t.CampaignId)
.Index(t => t.EmailId)
.Index(t => t.ContactGroupId);
CreateTable(
"dbo.EmailTemplates",
c => new
{
Id = c.Int(nullable: false, identity: true),
Name = c.String(),
Markup = c.String(),
Deleted = c.Boolean(nullable: false),
})
.PrimaryKey(t => t.Id);
}
public override void Down()
{
DropForeignKey("dbo.EmailSends", "EmailId", "dbo.Emails");
DropForeignKey("dbo.EmailSends", "ContactGroupId", "dbo.ContactGroups");
DropForeignKey("dbo.EmailSends", "CampaignId", "dbo.Campaigns");
DropForeignKey("dbo.Emails", "CampaignId", "dbo.Campaigns");
DropForeignKey("dbo.Contacts", "ContactGroupId", "dbo.ContactGroups");
DropIndex("dbo.EmailSends", new[] { "ContactGroupId" });
DropIndex("dbo.EmailSends", new[] { "EmailId" });
DropIndex("dbo.EmailSends", new[] { "CampaignId" });
DropIndex("dbo.Emails", new[] { "CampaignId" });
DropIndex("dbo.Contacts", new[] { "ContactGroupId" });
DropTable("dbo.EmailTemplates");
DropTable("dbo.EmailSends");
DropTable("dbo.Emails");
DropTable("dbo.Contacts");
DropTable("dbo.ContactGroups");
DropTable("dbo.Campaigns");
}
}
So what's the best way to fix this problem and apply this migration now?

Answer 1

Just remove the CreateTable method targeting dbo.Campaigns from the generated migration. For future migrations this will not be added because the model gets actually serialized in the __MigrationHistory table and it knows that you already took action on it.
This gets recorded on the Model column in __MigrationHistory table and it knows that Campaigns already exists and it will not try to create it again.
Hope this helps