WITH tot_subm AS (``
    SELECT 
        s.submission_date,
        COUNT(s.submission_id) AS total_submissions,
        h.hacker_id,
        h.name,
        ROW_NUMBER() OVER (
            PARTITION BY s.submission_date 
            ORDER BY COUNT(s.submission_id) DESC, h.hacker_id ASC
        ) AS r_numb
    FROM Hackers h
    INNER JOIN Submissions s ON s.hacker_id = h.hacker_id
    WHERE s.submission_date BETWEEN '2016-03-01' AND '2016-03-15'
    GROUP BY s.submission_date, h.hacker_id, h.name
)
SELECT 
    submission_date, 
    total_submissions, 
    hacker_id, 
    name        
FROM tot_subm    
WHERE r_numb = 1
ORDER BY submission_date;