CODEWITHSUNDEEP
sql-serverentity-frameworkentity-framework-migrations
Carlos Martinez
Carlos Martinez

Reputation: 4510

EF Code-First migrations ALTER TABLE DROP COLUMN Id failed because one or more objects access this column

I'm having trouble updating the database, when I apply the migration I'm getting this error:

The object 'PK_dbo.CostCenter' is dependent on column 'Id'.
ALTER TABLE DROP COLUMN Id failed because one or more objects access this column.

I just tried to add a virtual property (CostCenter) to this table to be able to get that data

[Table("Department")]
public class Department
{
    public int Id { get; set; }

    public string Code { get; set; }

    public virtual IList<Cost> Costs_Department { get; set; }
    public virtual CostCenter CostCenter { get; set; }
}

This is the CostCenter table

[Table("CostCenter")]
public class CostCenter
{
    public int Id { get; set; }

    public string Code { get; set; }

    [Required]
    public virtual Department Department { get; set; }
}

And another table related to Department

[Table("Cost")]
public class Cost
{
    public int Id { get; set; }

    ...

    public virtual Department Departament { get; set; }
    public virtual Material Material { get; set; }
}

The only change I added was the CostCenter property on the Department table, this is what VS created on the migrations file

public partial class CC : DbMigration
{
    public override void Up()
    {
        DropForeignKey("dbo.CostCenter", "Department_CostCenter_Id", "dbo.Department");
        DropIndex("dbo.CostCenter", new[] { "Department_CostCenter_Id" });
        DropColumn("dbo.CostCenter", "Id");
        RenameColumn(table: "dbo.CostCenter", name: "Department_CostCenter_Id", newName: "Id");
        DropPrimaryKey("dbo.CostCenter");
        AlterColumn("dbo.CostCenter", "Id", c => c.Int(nullable: false));
        AddPrimaryKey("dbo.CostCenter", "Id");
        CreateIndex("dbo.CostCenter", "Id");
        AddForeignKey("dbo.CostCenter", "Id", "dbo.Department", "Id");
    }

    public override void Down()
    {
        DropForeignKey("dbo.CostCenter", "Id", "dbo.Department");
        DropIndex("dbo.CostCenter", new[] { "Id" });
        DropPrimaryKey("dbo.CostCenter");
        AlterColumn("dbo.CostCenter", "Id", c => c.Int(nullable: false, identity: true));
        AddPrimaryKey("dbo.CostCenter", "Id");
        RenameColumn(table: "dbo.CostCenter", name: "Id", newName: "Department_CostCenter_Id");
        AddColumn("dbo.CostCenter", "Id", c => c.Int(nullable: false, identity: true));
        CreateIndex("dbo.CostCenter", "Department_CostCenter_Id");
        AddForeignKey("dbo.CostCenter", "Department_CostCenter_Id", "dbo.Department", "Id", cascadeDelete: true);
    }
}

I already have a relationship similar to this on other tables, so I don't know what's causing the problem this time

Upvotes: 5

Views: 6551

Answers (2)

curiousBoy
curiousBoy

Reputation: 6834

Per suggested solution above, once you are in the production, dropping db won't be the case.

In my case,

  • first I dropped the relation between two tables by editing my entities
  • Then create a migration script which will have these changes (dropping relation changes)
  • run update-database command.
  • Then edit your entity to drop the column.
  • Then create a migration script which will have most recent changes
    (dropping column)
  • After that, edit your entities to have the relation again
  • Then you can add another migration which will have the changes to re-create the relation between tables.
  • As final step, run update-database command to publish changes.

Is this the best solution?

  • I doubt about it.

Was it fixed the issue?

  • Yes.

Upvotes: 2

Gabriela Macias
Gabriela Macias

Reputation: 72

I faced similar issue and just remove all the previous migration files, create a new one and executed update-database command. If you can, also delete the database, Before it.

Upvotes: 3

Related Questions