即使在使用include之后，EF Core Navigation属性也未加载

Question

这是我的数据库设计

为此，我通过EF Core中的以下查询检索数据。

from u in _context.Users
                       from r in _context.Roles.Include("RoleApplicationActivity")
                       from raa in _context.RoleAppActivities.Include("Application").Include("Activity").Include("Role")
                       from app in _context.Applications.Include(a => a.RoleApplicationActivity)
                       from ac in _context.Activities.Include(a => a.RoleApplicationActivity)
                       where u.Id == id
                       select new FullUser
                       {
                           User = u,
                           Roles = u.Roles,
                           RoleAppActivity = r.RoleApplicationActivity

                       }

即使在我检查导航属性的值时使用包含它们也是空的。想知道我错过了什么。帮助赞赏。

在运行此查询之前，如果加载所有必需的实体，则EF Core会为我填充数据。想知道这是否是好方法。

_context.Applications.Load();
_context.Roles.Load();
_context.Activities.Load();