SQL: Return Aggregated Results based on some conditions

Question

I need help with making a conclusion in SQL Server based on some column's values, like status aggregation sort of. As an example, below is a table containing server tasks and their status.

If I want to return the aggregated status of each server here are the rules:

• if all the server tasks are at status 'SUBMITTED', then the aggregated server status is 'AWAITING'
• if all tasks are at status 'COMPLETED' - the aggregated status is 'DONE'
• if the above cases are not met, the aggregated server status is 'IN PROGRESS'

Example Table: Tasks

Server	Task_Status	Task
Server 1	RUNNING	1-1
Server 1	COMPLETED	1-2
Server 1	SUBMITTED	1-3
Server 2	COMPLETED	2-1
Server 2	COMPLETED	2-2
Server 3	SUBMITTED	3-1
Server 3	SUBMITTED	3-2

Example Query Result:

Server	Completion
Server 1	IN PROGRESS
Server 2	DONE
Server 3	AWAITING

So far I tried to use the following query with no success:

SELECT Server,
    CASE 
       WHEN Task_Status NOT IN ('RUNNING', 'COMPLETED') THEN 'AWAITING' -- Status SUBMITED
       WHEN Task_Status NOT IN ('RUNNING', 'SUBMITED') THEN 'DONE' -- Status COMPLETED
       ELSE 'IN PROGRESS'
    END Completion
FROM Tasks

Answer 1

You could use this:

WITH table_name AS
(
    SELECT 'Server 1' AS server, 'RUNNING' AS task_status, '1-1' AS task UNION ALL
    SELECT 'Server 1' AS server, 'COMPLETED' AS task_status, '1-2' AS task UNION ALL
    SELECT 'Server 1' AS server, 'SUBMITTED' AS task_status, '1-3' AS task UNION ALL
    SELECT 'Server 2' AS server, 'COMPLETED' AS task_status, '2-1' AS task UNION ALL
    SELECT 'Server 2' AS server, 'COMPLETED' AS task_status, '2-2' AS task UNION ALL
    SELECT 'Server 3' AS server, 'SUBMITTED' AS task_status, '3-1' AS task UNION ALL
    SELECT 'Server 3' AS server, 'SUBMITTED' AS task_status, '3-2' AS task 
)

SELECT server,
    CASE 
        WHEN COUNT(DISTINCT task_status) = 1 AND MAX(task_status) = 'SUBMITTED' THEN 'AWAITING'
        WHEN COUNT(DISTINCT task_status) = 1 AND MAX(task_status) = 'COMPLETED' THEN 'DONE'
        ELSE 'IN PROGRESS'
    END AS completion
FROM table_name
GROUP BY server
ORDER BY server;

Tested in sqlfiddle

Answer 2

select server, 
       case when count(distinct task_status) > 1 then 'in progress' 
            else case min(task_status) 
                   when 'completed' then 'done' 
                   when 'submitted' then 'awaiting' 
                   else 'some other result, perhaps an error' 
                 end 
        end result
  from your_table
group by server

Answer 3

select Server,
  case  max(Task_Status) when 'COMPLETED' then 'DONE' else 
    (case min(Task_Status) when 'SUBMITTED' then 'AWAITING' else 'IN PROGRESS' end )
  end as Completion
from Table_1
group by Server

result

Server  (Completion)
Server1     IN PROGRESS
Server2     DONE
Server3     AWAITING

Answer 4

SELECT 
  server,
  CASE
    WHEN status = 3 THEN 'IN PROGRESS'
    WHEN status = 2 THEN 'WAITING'
    WHEN status = 1 THEN 'DONE'
  END as completion
FROM (
  SELECT
    server,
    MAX( CASE 
       WHEN task_status = 'RUNNING' THEN 3 
       WHEN task_status = 'SUBMITTED' THEN 2 
       WHEN task_status = 'COMPLETED' THEN 1
       END
    ) status
  FROM Tasks
  GROUP BY server
) result

Answer 5

select 
    u.server,
    case 
        when u.cnt=u.cntCompleted then 'DONE'
        when u.cnt=u.cntSubmitted then 'AWAITING'
        else 'IN PROGRESS'
    end Completion
from
(
    select 
        server, 
        count(*) cnt,
        (select count(tstatus) from task t2 where t2.server=t1.server and t2.tstatus='SUBMITTED') cntSubmitted,
        (select count(tstatus) from task t2 where t2.server=t1.server and t2.tstatus='COMPLETED') cntCompleted
    from task t1
    group by server
) u

Answer 6

Thanks to Pham X Bach for table creation script.

You can go for step by step approach, where you calculate the different statuses count and later apply the logic as given below:

WITH table_name AS
(
    SELECT 'Server 1' AS server, 'RUNNING' AS task_status, '1-1' AS task UNION ALL
    SELECT 'Server 1' AS server, 'COMPLETED' AS task_status, '1-2' AS task UNION ALL
    SELECT 'Server 1' AS server, 'SUBMITTED' AS task_status, '1-3' AS task UNION ALL
    SELECT 'Server 2' AS server, 'COMPLETED' AS task_status, '2-1' AS task UNION ALL
    SELECT 'Server 2' AS server, 'COMPLETED' AS task_status, '2-2' AS task UNION ALL
    SELECT 'Server 3' AS server, 'SUBMITTED' AS task_status, '3-1' AS task UNION ALL
    SELECT 'Server 3' AS server, 'SUBMITTED' AS task_status, '3-2' AS task 
)

select server, case when Completed_Count = total_Count then 'Done'
                    when Submitted_Count = total_Count then 'Awaiting'
                    else 'In Progress' end as Completion
from
(
SELECT server, count(case when task_status = 'Completed' then 1 end) as Completed_Count,
count(case when task_status = 'Submitted' then 1 end) as Submitted_Count,
count(*) as total_count
FROM table_name
GROUP BY SERVER
) as t

server	Completion
Server 1	In Progress
Server 2	Done
Server 3	Awaiting