Hi Let's imagine these models, with ActiveRecord 4.0
class Parent < ActiveRecord::Base has_many :items end class Item < ActiveRecord::Base belongs_to :parent end I need to delete all items associated to one parent, without callback. I don't need to call #destroy, but only executing the appropriate SQL statement. First case : > parent.items.delete_all In Rails 4.1 delete_all on associations would not fire callbacks. It means if the :dependent option is :destroy then the associated records would be deleted without loading and invoking callbacks. Item Load (0.3ms) SELECT "items".* FROM "items" WHERE "items"."parent_id" = ? [["parent_id", 1]] (0.1ms) begin transaction SQL (1.1ms) DELETE FROM "items" WHERE "items"."id" = ? [["id", 44]] SQL (0.1ms) DELETE FROM "items" WHERE "items"."id" = ? [["id", 43]] SQL (0.1ms) DELETE FROM "items" WHERE "items"."id" = ? [["id", 42]] SQL (0.1ms) DELETE FROM "items" WHERE "items"."id" = ? [["id", 41]] ... (80.0ms) commit transaction I got one delete per item. Not perfect ! Now, let's try a workaround : > parent.items.scoped.delete_all DEPRECATION WARNING: Model.scoped is deprecated. Please use Model.all instead. SQL (0.1ms) DELETE FROM "items" WHERE "items"."parent_id" = ? [["parent_id", 1]] It works fine: only one statement. But according to the warning, it seems to not be the proper way to do. So, OK, let's try : > feed.items.all.delete_all DEPRECATION WARNING: Relation#all is deprecated. If you want to eager-load a relation, you can call #load (e.g. `Post.where(published: true).load`). If you want to get an array of records from a relation, you can call #to_a (e.g. `Post.where(published: true).to_a`). Item Load (0.3ms) SELECT "items".* FROM "items" WHERE "items"."feed_id" = ? [["feed_id", 1]] NoMethodError: undefined method `delete_all' for #<Array:0x007f87ae6fee00> from ~/.rvm/gems/ruby-2.0.0-p0@global/gems/rush-0.6.8/lib/rush/find_by.rb:16:in `method_missing' from (irb):24 from ~/.rvm/gems/ruby-2.0.0-p0@global/gems/railties-4.0.0/lib/rails/commands/console.rb:90:in `start' from ~/.rvm/gems/ruby-2.0.0-p0@global/gems/railties-4.0.0/lib/rails/commands/console.rb:9:in `start' from ~/.rvm/gems/ruby-2.0.0-p0@global/gems/railties-4.0.0/lib/rails/commands.rb:64:in `<top (required)>' from bin/rails:4:in `require' from bin/rails:4:in `<main>' I also tried to call #load : I got the same result as for the first case (too many DELETE statements). I can also do that : > Item.where(feed: feed).delete_all SQL (0.2ms) DELETE FROM "feed_items" WHERE "feed_items"."feed_id" = 1 Works fine. No warning. But let's forget the OOP. So.. What's the proper way ? -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To unsubscribe from this group and stop receiving emails from it, send an email to rubyonrails-talk+unsubscr...@googlegroups.com. To post to this group, send email to rubyonrails-talk@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rubyonrails-talk/2a3b9714-7dfc-415e-bc40-17e4573fddbe%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
