Interesting. Hopefully we can get an explanation as to why the increment methods are not done this way, and if the core team would be open to a patch.
- Alex On Monday, January 21, 2013 at 6:01 AM, Matt Huggins wrote: > Interestingly, ActiveRecord::CounterCache does this the appropriate way. > > https://github.com/rails/rails/blob/master/activerecord/lib/active_record/counter_cache.rb#L72 > > On Sunday, January 20, 2013 6:56:37 PM UTC-5, ajsharp wrote: > > The method is here: > > https://github.com/rails/rails/blob/master/activerecord/lib/active_record/persistence.rb#L288. > > > > The method takes the in-memory attribute value and increments it by the > > specified amount. A safer approach (from an isolation standpoint) would be > > to let the database determine the value. Instead of telling the database > > what value to persist in the database, the SQL can written (at least for > > postgres) so that the database will atomically increment a value: > > > > UPDATE "posts" SET view_count = view_count + 1 WHERE id=123; > > > > Currently, rails generates the following SQL: > > > > UPDATE "posts" SET "view_count" = 3, "updated_at" = '2013-01-20 > > 23:20:24.154852' WHERE "posts"."id" = 123 > > > > It would be great to see a method like this to perform atomic update > > operations for databases that support it. If there's support for this, I'm > > happy to write the patch. Thanks! > > -- > You received this message because you are subscribed to the Google Groups > "Ruby on Rails: Core" group. > To view this discussion on the web visit > https://groups.google.com/d/msg/rubyonrails-core/-/p2dAMnSuYIkJ. > To post to this group, send email to rubyonrails-core@googlegroups.com > (mailto:rubyonrails-core@googlegroups.com). > To unsubscribe from this group, send email to > rubyonrails-core+unsubscr...@googlegroups.com > (mailto:rubyonrails-core+unsubscr...@googlegroups.com). > For more options, visit this group at > http://groups.google.com/group/rubyonrails-core?hl=en. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Core" group. To post to this group, send email to rubyonrails-core@googlegroups.com. To unsubscribe from this group, send email to rubyonrails-core+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-core?hl=en.
