Grouping by year - mySQL -

i have mysql database date field.

i need find years in entries.

for example. if there 5 entries in 2014, , 1 in 2015. 2014 , 2015 output.

i think needs done group by have tried. not sure how complete inner query, think needs done.

select field_id_34 start_date exp_channel_data channel_id = 5 group year(field_id_34) 

can tell me if needs done? , possibly how?

if want know distinct years represented in data, want this:

select distinct year(field_id_34) year exp_channel_data channel_id = 5 

i have no idea field_id_34 is, i'm inferring post date field. also, assume have reasons filter, although not know reasons are. trust can fill in details on end.