CASE on two rows with identical IDs but different values

Question

I have the following table. What I need is an sql query that will analyze two/more rows with the same id and: (1) CASE 'Result' is the same for both rows, print 'Passed'; (2) CASE 'Result' is not the same for both rows, print 'Failed'.

ID  Result  
73  2000    Passed
73  2000    
43  2000    Failed
43  1003    

Is it all possible??

Answer 1

One option uses EXISTS :

SELECT DISTINCT ID
FROM yourTable t1
WHERE NOT EXISTS (SELECT 1 FROM yourTable t2 WHERE t1.ID = t2.ID AND t2.Result <> t1.Result);

Another option uses aggregation:

SELECT ID
FROM yourTable
GROUP BY ID
HAVING COUNT(DISTINCT Result) = 1;

Demo

Answer 2

If you want one row per id, then use group by :

select id,
       (case when min(result) = max(result) then 'Passed'
             else 'Failed'
        end) as flag
from t
group by id;

If you want the value on all rows of your original table, then it is simple:

select id,
       (case when not exists (select 1
                              from t t2
                              where t2.result) = t.result
                             )
             then 'Passed' else 'Failed'
        end) as flag
from t
group by id;

However, putting the result on one row is problematic. There is no way to distinguish the rows, so it is more challenging (not impossible, but I suspect one of the above solves your real problem).

Answer 3

Try below:

select id, case when count (distinct result)=1 then 'Passed' else 'Failed' end
group by id