SQL Multiple COUNT() from two tables, within a LEFT JOIN

Question

i have three tables, i want to select all data from one of the tables, and also collect a COUNT of how many times that specific row of data is linked in the other two tables.

So, SELECT all data from site_projects. Then return a COUNT of site_project_members WHERE site_projects.id = site_project_members.pid and also return a COUNT of site_project_tasks WHERE site_projects.id = site_project_members.pid

I hope i'm making sense, to the query, it looks correct. and it querys the database (MySQL) with no problems. Except it returns a sum of both of the counts as both things. (see below the table structures)

site_projects

id | title     | desc      | start      | deadline   | progress

1  | Project 1 | a project | 1321748906 | 1329847200 | 20

site_project_members

id | pid | uid | img | hidden
1  | 1   | 1   | 1   | 0
2  | 1   | 2   | 2   | 0

site_project_tasks

id | pid | desc   | completed
1  | 1   | Task 1 | 1
1  | 1   | Task 2 | 0

Here is my query:

SELECT p.`id`, p.`title`, p.`desc`, p.`progress`, p.`start`, p.`deadline`, COUNT(m.`id`) as `members`, COUNT(t.`id`) as `tasks` FROM `site_projects` p LEFT JOIN `site_project_members` m ON p.`id`=m.`pid` LEFT OUTER JOIN `site_project_tasks` t ON p.`id`=t.`pid` ORDER BY p.`id` ASC

The result i get is:

id | title     | desc      | progress | start      | deadline   | members | tasks
1  | Project 1 | a project | 20       | 1321748906 | 1329847200 | 4       | 4

Both of the "4" values should be 2. however they are not :S Anyone able to help? Much Appreciated

Thanks, Dan

Answer 1

SELECT p.id , p.title , p.desc , p.progress , p.start , p.deadline , 
   COALESCE( m.cnt, 0 ) AS members,
   COALESCE( t.cnt, 0 ) AS tasks
FROM site_projects p
LEFT JOIN 
  ( SELECT pid, COUNT(*) AS cnt FROM
    site_project_members
    GROUP BY pid ) m
ON p.id = m.pid
LEFT JOIN
  ( SELECT pid, COUNT(*) AS cnt FROM
    site_project_tasks
    GROUP BY pid ) t
ON p.id = t.pid
ORDER BY p.id ASC

Answer 2

SELECT p.`id`, p.`title`, p.`desc`, p.`progress`, p.`start`, p.`deadline`,
     (SELECT COUNT(*) FROM site_project_members m WHERE p.`id`=m.`pid`) AS `members`,
     (SELECT COUNT(*) FROM site_project_tasks t WHERE p.`id`=t.`pid`) AS `tasks`
FROM `site_projects` p
ORDER BY p.`id` ASC

That should really do the trick.