How to organize MySQL DB to allow an arbitrary counter for clicks, visits, etc in past 24 hours?
3 suggestions...

Don't store all of "http://count.io/vb/product37/1468038731", it wastes space and time.  Trim it down to just the timestamp.

Don't store the time, bump a counter for the day (or hour, if you prefer).

Don't store anything, parse the web server logs later.

Now let me approach it a different way... What is the minimal information you want?  Exact times of all hits?  Running counter of hits?  Daily counts?  Keep in mind what information can be derived from what other info.  Hourly counts --> daily counts.  Running counter --> daily counts (if you grab the count every midnight).  Etc.