mysql group by show count 0 not sure if I can left join here -

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i have query , want return row when count 0

select count(day) count, day `table` group `day`

other stackoverflow answers need left join.
don't know how in scenario.

create table thedays (   aday varchar(20) not null );  create table sales (   id int auto_increment primary key,     aday varchar(20) not null,     prodid int not null,     qty int not null );  insert thedays values ('sunday'),('monday'),('tuesday'),('wednesday'),('thursday'),('friday'),('saturday'); insert sales(aday,prodid,qty) values ('tuesday',101,4),('thursday',107,2);  select d.aday thedays d left outer join sales s on d.aday=s.aday s.aday null  +-----------+ | aday      | +-----------+ | sunday    | | monday    | | wednesday | | friday    | | saturday  | +-----------+

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