Simple SQL query: sum the values ​​of the same column in one go

Question

I have created this query:

SELECT table1.id, b.sum 
FROM table1 
CROSS JOIN (SELECT SUM(id) sum 
            FROM table1) b 
ORDER BY id DESC;

But this will produce the following results:

id	sum
3	6
2	6
1	6

Sum value is printed only once. can you help me solve it.

But I want this result:

id	sum
3	6
2
1

Answer 1

This should do the trick:

select 
   id,
   CASE WHEN id=(max(id) over()) 
        THEN sum(id) over (order by id) END as 'sum' 
from cte1
order by id desc;

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