Displaying rows with count 0 with mysql group by

Question

I have two tables in MySql Company : (cname,city) works : (ename,cname,salary)

I want to display number of employees working for every company, even if that number i

Answer 1

There is another way to do so with subquery, here is a sample from my case:

select count(`order_id`) as cnt
from (
    select `order_id` from `room_bookings`
    where `room_id` = 3 and `day_id` = 20180201 
    group by `order_id`
) as b;