Code migration unexpectedly tries to rename table - entity-framework-migrations

Question

I want to implement a change log as advised in
Dev Express XAF T474899
I am using the security system generated by the XAF new solution wizard
I have defined some business objects to store the change log information.
One of these objects stores a link to the user
public virtual User User { get; set; }
On generating the code migration I am surprised to see the Up() method add the following
RenameTable(name: "dbo.UserRoles", newName: "RoleUsers");
DropPrimaryKey("dbo.RoleUsers");
AddPrimaryKey("dbo.RoleUsers", new[] { "Role_ID", "User_ID" });
On another occasion I found the following in an Up()
RenameTable(name: "dbo.EventResources", newName: "ResourceEvents");
// lots of other stuff
DropPrimaryKey("dbo.ResourceEvents");
AddPrimaryKey("dbo.ResourceEvents", new[] { "Resource_Key", "Event_ID" });
On both occasions the code that creates the entities is a Dev Express libary.
I have cross posted this question to Dev Express Support
The Dev Express business objects are defined in DevExpress.Persistent.BaseImpl.EF;
My DbContext context refers to them as
public DbSet<Role> Roles { get; set; }
public DbSet<User> Users { get; set; }
The meta data for Role shows
The meta data for User shows
My own business classes contain
namespace SBD.JobTalk.Module.BusinessObjects
{
[NavigationItem("Configuration")]
[DisplayName("Staff")]
[DefaultProperty("Summary")]
[ImageName("BO_Employee")]
[Table("Staff")]
public class Staff : BasicBo
{
public Staff()
{
Person = new Person();
}
public virtual Person Person { get; set; }
[StringLength(100, ErrorMessage = "The field cannot exceed 100 characters. ")]
[scds.Index("IX_Staff_UserName", 1, IsUnique = true)]
public string UserName { get; set; }
[NotMapped]
public string Summary => $"{Person.FirstName} {Person.LastName}";
//public virtual User User { get; set; }
}
}
public abstract class BasicBo : IXafEntityObject
{
[Browsable(false)]
[Key]
public virtual int Id { get; set; }
public virtual void OnCreated()
{
}
public virtual void OnSaving()
{
}
public virtual void OnLoaded()
{
}
}
If I un-comment the code to have the User property inside Staff, and generate a migration, the migration Up is
public override void Up()
{
RenameTable(name: "dbo.UserRoles", newName: "RoleUsers");
DropPrimaryKey("dbo.RoleUsers");
AddColumn("dbo.Staff", "User_ID", c => c.Int());
AddPrimaryKey("dbo.RoleUsers", new[] { "Role_ID", "User_ID" });
CreateIndex("dbo.Staff", "User_ID");
AddForeignKey("dbo.Staff", "User_ID", "dbo.Users", "ID");
}
[Update]
Interestingly there are more Dev Express tables than I first thought.
The primary keys are Identity.
I think am using Standard Authentication created before Dev Express added the Allow/Deny ability (V16.1)
[Update]
When I create a new project with the above settings, here is the DbContext.
using System;
using System.Data;
using System.Linq;
using System.Data.Entity;
using System.Data.Common;
using System.Data.Entity.Core.Objects;
using System.Data.Entity.Infrastructure;
using System.ComponentModel;
using DevExpress.ExpressApp.EF.Updating;
using DevExpress.Persistent.BaseImpl.EF;
using DevExpress.Persistent.BaseImpl.EF.PermissionPolicy;
namespace XafApplication1.Module.BusinessObjects {
public class XafApplication1DbContext : DbContext {
public XafApplication1DbContext(String connectionString)
: base(connectionString) {
}
public XafApplication1DbContext(DbConnection connection)
: base(connection, false) {
}
public XafApplication1DbContext()
: base("name=ConnectionString") {
}
public DbSet<ModuleInfo> ModulesInfo { get; set; }
public DbSet<PermissionPolicyRole> Roles { get; set; }
public DbSet<PermissionPolicyTypePermissionObject> TypePermissionObjects { get; set; }
public DbSet<PermissionPolicyUser> Users { get; set; }
public DbSet<ModelDifference> ModelDifferences { get; set; }
public DbSet<ModelDifferenceAspect> ModelDifferenceAspects { get; set; }
}
}

Answer 1

OK, I will take a stab :) Your Up() code is trying to rename the table UserRoles to RoleUsers. This means you have a prior migration where UserRoles was the table name - probably from your DevEx stuff. This could happen if they changed their models in an upgrade. The current models are expecting RoleUsers etc. so you need to get there.
So first option is let the migration do the renaming to match the underlying model. I assume this didn't work or causes other issues?
You might be able to 'fool' entity framework into using the old tables with fluent code or annotations, but if it has new columns or relationships that won't work.
What I would do is this:
1) Create a new test project with the same references you had and
copy your context and DbSets. Point the connection string to a
new database.
2) Add a migration and script it out:
update-database -Script.
3) Examine this script a use it to create
the objects needed in your database. Migrate data from the old
tables to new if needed.
4) Remove the old tables
5) In your actual
project add a migration to resync your models:
add-migration SyncDevExUpdate -IgnoreChange, update-database
Now you will have the tables your models expect.