sql - MySQL distinct and left, right -

i have table day column this:

2011-04-28, 2011-04-29 ... day           count  name surname 2011-04-28    8       titi tutu 2011-04-28     12     tutu toto 2011-04-27     2      tutu toto 2011-03-12     10     tutu toto 

i can obtain distinct day not month , year.

select distinct(day) table day between "2011-03-01" , "2011-04-28"; 

i want distinct month , year.

can me?

thanks

select distinct extract(year_month `day`) yearmonth table day between '2011-03-01' , '2011-04-28';