Question

My website is like stackoverflow, there are many questions. I want to record how many times a question has been visited. I have a column called “view_count” in the question table to save it.

If a user visits a question many times, the view_count should be increased only 1. So I have to record which user has visited which question, and I think it is too much expensive to save this information in the database because the records will be huge. So, I would like to keep the information in memory and only persist the number to the database every 10 minutes.

I have searched about “cache” in Rails, but I haven’t found an example. I would like a simple sample of how to do this, thanks for help~

Answer 1

This article is pretty amazing – if you have the opportunity to use Memcache I think it would help you greatly: http://www.ridingtheclutch.com/2009/01/08/cache-anything-easily-with-rails-and-memcached.html

if you could do something like:

if CACHE.get(key) >= 10:
  send to db
  CACHE.set(key, 0, 1.hour)
else:
  newcount = CACHE.get(key) + 1
  CACHE.set(key, newcount, 1.hour)
end