Question

I use ASP.MVC / EF in my project.

The domain model as below:

public class Post
{
     public int Id {get;set;}
     public string Abstract {get;set;}
     public string Content {get;set;}
}

and the view model is

public class PostListView
{
     public int Id {get;set;}
     public string Abstract {get;set;}
}

statemens in action to get model:

 db.Posts.Where(...).Select(p=>new PostListView
 {
       Id = p.Id,
       Abstract = p.Abstract
 });

When I check the SQL generated by Entity Framwork, the select statement includes all three columns. Is there some way to make EF generate more effective SQL statements that only select the fields needed by view model?

Thank you!

Answer 1

You can do like this

 var postQuery = from p in db.Posts
                                      select new { p.Id,p.Abstract};

And the enumerate collection

foreach (var p in postQuery  ){
// fill your view model here

}