Show null values in group by query as zero

Question

I have two tables, tasks and status. Tasks table have columns task_id, project_id task_content and status_id. Status table have columns status_id and status_name. I want to get query which takes all status names and counts how much are there tasks with that status names. My query looks like this:

EDIT: i forgot to add project_id. Query needs to check only tasks within one project.

SELECT s.status_name, COUNT(t.status_id) AS tasks
FROM status s
LEFT JOIN tasks t
ON s.status_id = t.status_id
WHERE t.project_id = 1
GROUP BY s.status_name

My query is working good, but when there are no tasks with one of statuses this status is left out from query, i want it to show zero like:

    status name | tasks 
     status 1   |  3 
     status 2   |  2
     status 3   |  0

but my query looks like this:

status name | tasks 
 status 1   |  3 
 status 2   |  2

Answer 1

Thanks everyone for help, i found solution. I will post it for everyone who will have same or similar problem in future. Using 'WHERE' mess up my left join so there is workaround:

SELECT s.status_name, (IFNULL(COUNT(t.task_id), 0)) AS tasks
FROM status s 
LEFT OUTER JOIN tasks t
ON  s.status_id = t.status_id 
AND t.project_id = 1 
GROUP BY s.status_name