Question

I wrote this task to populate a table. The “Flight” table is pretty big (23000 posts). But I get this weird error when we move through the loop the second time.

Here’s the code:

desc "Compute the AirlineTerminal Table"
task :populate_airlineterminals => :environment do
    #first delete content
    AirlineTerminal.destroy_all
    allFlights = Flight.all

        #AFTER ONE ITERATION THE ERROR HAPPENS
    allFlights.each do |f|
        atTerminal = AirlineTerminal.where(:airline_id => f.airline_id, :airport_id => f.airport_id, :terminal => f.terminal).first
        if atTerminal.nil?
            atTerminal = AirlineTerminal.new
            atTerminal.airport_id = f.airport_id
            atTerminal.airline_id = f.airline_id
            atTerminal.terminal = f.terminal
        end
        atTerminal.count++

        atTerminal.save #so far so good
    end
end

This is what happens when I run the script, after one trip through the loop it crashes.

$ rake populate_airlineterminals
rake aborted!
undefined method `+@' for true:TrueClass

Answer 1

Although I do not know the error my bet is that

atTerminal++

is the culprit. As far as I know ++ is not defined in ruby. You have to use

atTerminal += 1

unless of course you have defined it yourself. Maybe it causes errors while interpreting the code. Try it in irb.