title: EF Core - Ignore field (do not create a column in db) but fill it from raw query
body: <p>I have an entity with a field that should not be created in the database, but should be filled from a stored procedure.</p>
  
  <pre><code>public class Item 
  {
      public int Id {get; set;}
      public int CalculatedField {get; set;}
  }
  </code></pre>
  
  <p>Then I want to fill it with a stored procedure</p>
  
  <pre><code>var items = _db.Items.FromSqlRaw("select * from StoredProcedure()").ToList()
  </code></pre>
  
  <p>But if I use <code>[NotMapped]</code> attribute or <code>.Ignore</code> fluent option - the EF the field completely, and even though my stored procedure returns <code>CalculatedField</code>, EF does not use it.</p>
  
  <p>Is there any way to achieve this behavior?</p>