Import CSV with long numbers in Rails - ruby-on-rails

Question

I am going to keep this question simple.
I am trying to import a CSV file into my application.
The file has long numbers in it such as :"9405510200830754182150"
but when the file is imported the data looks like this: "9.40551e+21"
does anyone know how to get around this?
Here is the code I am using
CSV.foreach(file.path, headers: true) do |row|
puts "row: #{row.inspect}"
end
UPDATE
Thank you for the comments, I am not sure why CSV is converting that number into a float i need to keep it as a string.
I should clarify that I am using Rails 3.2.18 for this project
If you want to reproduce my code:
1.create CSV with 9405510200830754182150 in it
2.run this code to terminal:
file = File.join(Rails.root, 'tracking.csv')
CSV.foreach(file, headers: true) do |row|
puts "row: #{row.inspect}"
end
I need to be able to keep "9405510200830754182150" is a string since this is a tracking number of an order and needs to be stored in the database

Answer 1

Are you sure that "9.40551e+21" is not a visual approximation? Try this:
CSV.foreach(file.path, headers: true) do |row|
puts row['my_numeric_header']
end

Answer 2

It's supposed to treat everything in a CSV file as a string by default. You could try the converters: numeric option
CSV.foreach(file.path, headers: true, converters: :numeric) do |row|
puts "row: #{row.inspect}"
end
Which will interpret numbers into the appropriate types. Otherwise you might have to debug the CSV module code to figure out what's going on.

Answer 3

The :float converter converted your number to a Float for you. Unfortunately Float cannot hold such a large number, see comments...
[14] pry(main)> val = CSV::Converters[:float].('9405510200830754182150')
=> 9.405510200830755e+21
[15] pry(main)> val.class
=> Float
[16] pry(main)> "%d" % val
=> "9405510200830754553856"
[17] pry(main)> "%f" % val
=> "9405510200830754553856.000000"