Error when using 'find_all_by_'

Question

I get an error while using find_all_by_

controller
@books = Book.find_by_author_id(4)

View
<%= @books.name %>

This works. But when I replace find_by_ with find_all_by_ I get this error

undefined method `name'

I want to use find_all_by_ to fetch all the books corresponding to author_id=4

Answer 1

Controller
@books = Book.find_all_by_author_id(4)

View
<%= @books.map(&:name).join(', ') %>

you are getting an Array of records. And Array does not have the name method.