Lấy cảm hứng từ các câu trả lời khác, nhưng có lẽ được tổ chức tốt hơn:
SELECT *,
brcht + cana + font + nr AS total
FROM (SELECT insee,
annee,
SUM(Coalesce(brcht.nb, 0)) brcht,
SUM(Coalesce(cana.nb, 0)) cana,
SUM(Coalesce(font.nb, 0)) font,
SUM(Coalesce(nr.nb, 0)) nr
FROM brcht
full outer join cana USING (insee, annee)
full outer join font USING (insee, annee)
full outer join nr USING (insee, annee)
GROUP BY insee,
annee) t
ORDER BY insee,
annee;
Trao tặng:
insee | annee | brcht | cana | font | nr | total
--------+-------+-------+------+------+----+-------
036223 | 2013 | 0 | 0 | 0 | 1 | 1
036223 | 2014 | 0 | 0 | 0 | 1 | 1
036223 | 2017 | 0 | 1 | 0 | 0 | 1
086001 | 2013 | 0 | 0 | 0 | 1 | 1
086001 | 2014 | 0 | 0 | 0 | 2 | 2
086001 | 2015 | 0 | 0 | 0 | 4 | 4
086001 | 2016 | 0 | 2 | 0 | 2 | 4
(7 rows)
