Filtering by window function result in Postgresql

Question

Ok, initially this was just a joke we had with a friend of mine, but it turned into interesting technical question :)

I have the following stuff table:

Answer 1

I don't know if this qualifies as "more elegant" but it is written in a different manner than Cybernate's solution (although it is essentially the same)

WITH window_table AS 
( 
   SELECT s.*, 
          sum(volume) OVER previous_rows as total
   FROM stuff s
   WINDOW previous_rows as 
        (ORDER BY priority desc ROWS between UNBOUNDED PRECEDING and CURRENT ROW)
) 
SELECT * 
FROM window_table
WHERE total < 1000
ORDER BY priority DESC 

If by "more elegant" you mean something that avoids the sub-select, then the answer is "no"

Answer 2

I haven't worked with PostgreSQL. However, my best guess would be using an inline view.

SELECT a.*
FROM (
    SELECT s.*, sum(volume) OVER previous_rows AS total
    FROM stuff AS s
    WINDOW previous_rows AS (
         ORDER BY priority desc
         ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
    )
    ORDER BY priority DESC
) AS a
WHERE a.total < 1000;