Convert timestamp to X days X hours X minutes ago

I've created a stored procedure in MySQL Server 5.1.

How can I convert a timestamp to a string that represents the da开发者_如何学Pythonys, hours, and minutes difference between that timestamp and now?

For example, if the timestamp is 5 hours and 3 minutes ago I'll get '5 hours 3 minutes ago'.

select date_format(timediff(current_timestamp,last_timestamp), 
'%k hours, %i minutes, %s seconds ago');

If you want more luxury you can do something like:

select concat
  (
  if(date_format(timediff(ts1,ts2)'%k')='0'
     ,'',date_format(timediff(ts1,ts2)'%k hours'),
  if(date_format(timediff(ts1,ts2)'%i')='0'
     ,'',date_format(timediff(ts1,ts2)'%k minutes'),
  if(date_format(timediff(ts1,ts2)'%s')='0'
     ,'',date_format(timediff(ts1,ts2)'%k seconds')
  ) 

Plus a few extra spaces here and there.
If one of the timestamps is null naturally the result will also be null, you'll have to make sure it is not, or use ifnull(`timestamp`,now()) to fix that.

See: http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_timediff

Have a look at the MySQL reference page for date and time functions at

http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_from-unixtime

Edit: Since I assume you are using Unix timestamps, the way to go is

FROM_UNIXTIME(timestamp, format)