FULL OUTER JOIN do łączenia tabel z PostgreSQL

Zainspirowany innymi odpowiedziami, ale być może lepiej zorganizowany:

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; 

Dając:

 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)