SQL View with count from multiple tables - sql

Question

I have a nodejs app with SQL Server. I want to be able to have a View where I can get a tally of number of users, projects, tasks for multiple organization. Let's say I have 4 tables as follows:
TABLES:
Organization: orgId(PK), orgName
Project: projId(PK), orgId(FK), projName
Tasks: taskId(PK), projId(FK), taskName
Users: userId(PK), orgId(FK), userName
VIEW:
OrganizationStats: numberOfProjects, numberOfUsers, numberOfTasks orgId(FK)
It was suggested to use something like this:
CREATE VIEW dbo.vw_OrganisationStats AS
SELECT {Columns from OrganizationStats},
P.Projects AS NumProjects
FROM dbo.OrganizationStats OS
CROSS APPLY (SELECT COUNT(*) AS Projects
FROM dbo.Projects P
WHERE P.OrgID = OS.OrgID) P;
My problem is I am having problem adding the count for Tasks and Users in addition to the Project within the same View. Any help would be appreciate it.
**Sample Data:**
* **Organization**: orgId(PK), orgName
1, ACME Inc.
2, Walmart Inc.
3, YoYo Inc.
* **Project**: projId(PK), orgId(FK), projName
1, 1, ACME Project 1
2, 1, ACME Project 2
3, 2, Walmart Project 1
4, 2, Walmart Project 2
5, 2, Walmart Project 3
* **Tasks**: taskId(PK), projId(FK), taskName
1, 1, Task 1 for Acme Project 1
2, 1, Task 2 for Acme Project 1
3, 4, Task 1 for Walmart Project 2
* **Users**: userId(PK), orgId(FK), userName
1, 1, Bob
2, 1, Alex
3, 1, Jim
4, 2, John
Expected Result
VIEW:
* **OrganizationStats**: numberOfProjects, numberOfUsers, numberOfTasks orgId(FK)
2, 3, 2, 1
3, 1, 1, 2
0, 0 ,0, 3

Answer 1

Consider:
select o.orgid,
count(distinct p.projid) as cnt_projects,
count(distinct u.userid) as cnt_users,
count(*) cnt_tasks
from organization o
inner join projects p on p.orgid = o.orgid
inner join users u on u.orgid = o.orgid
inner join tasks t on t.projid = p.projid and t.userid = u.userid
group by o.orgid

Answer 2

SELECT O.orgId
,COUNT(DISTINCT U.userId) AS 'numberOfUsers'
,COUNT(DISTINCT P.projId) AS 'numberOfProjects'
,COUNT(DISTINCT T.taskId) AS 'numberOfTasks'
FROM Organization O
LEFT JOIN Users U ON O.orgId = U.orgId
LEFT JOIN Project P ON O.orgId = P.orgId
LEFT JOIN Tasks T ON P.projId = T.projId
GROUP BY O.orgId
SCRIPT USED:
CREATE TABLE Organization (orgId INT , orgName VARCHAR(20))
CREATE TABLE Project(projId INT, orgId INT, projName VARCHAR(20))
CREATE TABLE Tasks (taskId INT, projId INT, taskName VARCHAR(20))
CREATE TABLE Users (userId INT, orgId INT, userName VARCHAR(20))
INSERT INTO Organization VALUES (1, 'ORG 1'), (2, 'ORG 2')
INSERT INTO Organization VALUES (3, 'ORG 3')
INSERT INTO Project VALUES (1,1, 'PRO 11'), (2,2, 'PRO 21'), (3,2, 'PRO 22')
INSERT INTO Tasks VALUES (1, 1, 'TASK 11'), (2, 1, 'TASK 21'), (3, 2, 'TASK 32'), (4, 2, 'TASK 42'), (5, 2, 'TASK 52')
INSERT INTO Users VALUES (1, 1, 'USER 11'), (2, 1, 'USER 12'), (3, 2, 'USER 21')
RESULTS :
+-------+---------------+------------------+---------------+
| orgId | numberOfUsers | numberOfProjects | numberOfTasks |
+-------+---------------+------------------+---------------+
| 1 | 2 | 1 | 2 |
+-------+---------------+------------------+---------------+
| 2 | 1 | 2 | 3 |
+-------+---------------+------------------+---------------+
| 3 | 0 | 0 | 0 |
+-------+---------------+------------------+---------------+