Hassan Schroeder wrote in post #1149759: > On Sun, Jun 15, 2014 at 1:29 AM, Ronald Fischer <li...@ruby-forum.com> > wrote: > (assume that ) box = Box.find(box_id) > > box.cards # has the cards you want *if* you need all the attributes > > box.cards.pluck(:id) # builds a query to fetch *only* the card ids
May I ask how this works (internally)? For pluck() to be applied, Ruby has first to execute box.cards() to get an Array of the cards. Unless the Card objects are implemented as proxies, which only fetch their data from the database if one asks for it, I would at this point, at least temporarily, have all the selected Card data in memory, isn't it? Ronald -- Posted via http://www.ruby-forum.com/. -- 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/2845a06ed41c1407411b5ac77b8318b0%40ruby-forum.com. For more options, visit https://groups.google.com/d/optout.
