mysql - Return a zero for a day with no results -

i have query returns total of users registered each day. problem if day had no 1 register doesn't return value, skips it. rather returned zero

this query far

select count(*) total users created_at < now() , created_at >  date_sub(now(), interval 7 day) , owner_id = ? group day(created_at)  order created_at desc 

edit

i grouped data count each day- date range, wanted total users registered previous 7 days

a variation on theme "build on 7 day calendar inline":

select d, count(created_at) total (select date_sub(now(), interval d day) d         (select 0 d      union select 1      union select 2      union select 3      union select 4      union select 5      union select 6      ) d ) d left join users on date(created_at) = date(d) owner_id = ? or  owner_id null group d  order d desc 

i don't have table structure @ hand, need adjustment probably. in same order of idea, see use now() reference date. that's adjustable. anyway that's spirit...

see live demo http://sqlfiddle.com/#!2/ab5cf/11