ruby on rails - DateTime.now or Time.now?

Question

Which of the two should I be using in my Rails application:

DateTime.now or Time.now

Is there any harm in using both in the application?

Can there ever be any differences between the two in case of the above (now) example? (On my current system they are both showing the same time)

question from:https://stackoverflow.com/questions/5600667/datetime-now-or-time-now

Answer 1

In reference to Time.now (not DateTime.now):

The object created will be created using the resolution available on your system clock, and so may include fractional seconds.

a = Time.new      #=> Wed Apr 09 08:56:03 CDT 2003
b = Time.new      #=> Wed Apr 09 08:56:03 CDT 2003
a == b            #=> false
"%.6f" % a.to_f   #=> "1049896563.230740"
"%.6f" % b.to_f   #=> "1049896563.231466"