Shortest average posts by day

select date_format(max(time), '<a href="/%Y/%m/%d/">%d/%m/%Y</a>') as Day, avg(length(comment)) as AverageLength, count(*) as PostCount from columnc group by to_days(time) order by AverageLength limit 20

Day AverageLength PostCount
14/08/2007 4.5000 2
28/01/2007 5.0000 2
05/01/2010 5.0000 1
02/12/2007 5.0000 1
21/06/2012 5.0000 1
08/11/2008 5.0000 1
16/12/2009 5.0000 1
07/12/2007 5.5000 2
04/02/2012 5.5000 2
26/05/2007 6.0000 1
13/05/2006 6.7500 4
21/06/2010 7.0000 1
25/06/2007 8.0000 1
25/08/2003 8.0000 1
28/03/2005 8.0000 1
07/08/2003 8.0000 2
28/01/2006 8.6667 3
07/02/2003 9.0000 1
24/09/2003 9.0000 1
16/09/2007 11.0000 1