更新 rails 中 model 的所有数据

Question

For example we have:

class PublicLibrary  < ActiveRecord::Base
  has_many :books
end


class Book  < ActiveRecord::Base
  belongs_to :public_library
end

If we want do update all books in PublicLibrary, we can add to PublicLibrary model

accepts_nested_attributes_for :books, :allow_destroy => true, :reject_if=>:all_blank

And now we can do something like this

library=PublicLibrary.find(ID)
library.update_attributes(:books_attributes=>{<bunch of books here>})

And all related books will be updated, some books'll be removed and some new books will be inserted in table books

Now I have some model Book, that doesn't have relation with PublicLibrary:

class Book  < ActiveRecord::Base
end

I have an admin panel that show all books in one big-big table and want to update/delete/insert new books just by one click, so I want something like

Book.bulk_update({...books...}) 

Or working with subset (don't sure is I really need it, but if we can do that...why not to know how?)

books_to_update=Book.where(...).bulk_update({...books...})

Of course Book may have some nested models.

Do you have any ideas? PS Currently I have only idea of having some parent and do update for it...

Answer 1

your {...books...} hash either has multiple books in it for which you want

books.each { |id, book| Book.find(id).update_attributes(book) }

or you want to do a real bulk update (meaning same update to all books in action) then you can use http://apidock.com/rails/ActiveRecord/Relation/update_all