Iterating through every record in a database - Ruby on Rails / ActiveRecord

Question

n00b question. I'm trying to loop through every User record in my database. The pseudo code might look a little something like this:

def send_notifications          render :nothing => true          # Randomly select Message record from DB         @message = Message.offset(rand(Message.count)).first          random_message = @message.content          @user = User.all.entries.each do             @user = User.find(:id)              number_to_text = ""              @user.number = number_to_text #number is a User's phone number             puts @user.number          end      end 

Can someone fill me in on the best approach for doing this? A little help with the syntax would be great too :)

Answer 1

Here is the correct syntax to iterate over all User :

User.all.each do |user|   #the code here is called once for each user   # user is accessible by 'user' variable    # WARNING: User.all performs poorly with large datasets end 

To improve performance and decrease load, use User.find_each (see doc) instead of User.all. Note that using find_each loses the ability to sort.

Answer 2

Also a possible one-liner for same purpose:

User.all.map { |u| u.number = ""; puts u.number }