Question

There are times where I have to display the relationship between two entities. Question is, should you retrieve the data all in one query (with a join statement)?

For example, I have the entity User and Picture. A picture is created by one user. If I wanted to display list of picture names, and who uploaded the certain picture.

Two approaches:

1) Using Entity Framework relationship, where Pictures is an entity, and it has a User property (the user that created it). The User is an entity too.

foreach(var picture : context.Pictures.all){
  picture.name
  picture.user.name
}

---

2) Combining Picture & User into one POCO object and return that to the controller.
Controller:

foreach(var pictureUser : dal.GetPictureUsers){
  pictureUser.PictureName
  pictureUser.UserName
}

GetPictureUsers()
{
  PictureUser pictureUserPoc = new PictureUsersql.Include("Picture").include("User").Select(sa=> new PictureUser {
                                                                              PictureName = sa.PictureName, 
                                                                              UserName = sa.UserName});
}

The latter one was suggested in order to increase performance. Personally I would have written it in the former way since you do not couple what you want in the View logic (having Picture and User relationship printed) in the data access layer.

I hope I have stated the question clearly.
Thanks!

Answer 1

@foreach (var profile in Model)
{
  @Html.DisplayFor(model=>profile.PictureName);
  @Html.DisplayFor(model=>profile.User.Name);
}

The Model represents the Pictures; if you strongly type the view then you can use it.