title: Is eager loading same as join fetch?
body: <p>Is eager fetch same as join fetch?</p>
  
  <p>I mean whether eagerly fetching a has-many relation fires 2 queries or a single join query?</p>
  
  <p>How does rails active record implement a join fetch of associations as it doesnt know the table's meta-data in first hand (I mean columns in the table)? Say for example i have </p>
  
  <p>people - id, name
  things - id, person_id, name</p>
  
  <p>person has one-to-many relation with the things. So how does it generate the query with all the column aliases even though it cannot know it when i do a join fetch on people?</p>