Reviewed flags of top videos solution

-- Reviewed flags of top videos
-- https://platform.stratascratch.com/coding/2103-reviewed-flags-of-top-videos
SELECT
    video_id,
    COUNT(flag_review.reviewed_by_yt)
FROM
    user_flags
    INNER JOIN flag_review ON flag_review.flag_id = user_flags.flag_id
GROUP BY
    video_id
HAVING
    COUNT(video_id) = (
        SELECT
            MAX(Count)
        FROM (
            SELECT
                COUNT(*) AS Count
            FROM
                user_flags
                INNER JOIN flag_review ON flag_review.flag_id = user_flags.flag_id
            GROUP BY
                video_id
        ) AS CntList
    )