Ça devrait ressemblé a qq. chose de pareille
SELECT g1.n_b_exp, g1.ano_b_exp, g1.essence,
count(g1.n_abat) AS nbr1_grumes,
sum(g1.volume_sa_def) AS t1_volume_sa_def,
sum(g1.volume_aa_def) AS t1_volume_aa_def,
g2.n_b_exp, g2.ano_b_exp, g2.essence,
count(g2.n_abat) AS nbr2_grumes,
sum(g2.volume_sa_def) AS t2_volume_sa_def,
sum(g2.volume_aa_def) AS t2_volume_aa_def
FROM
grume g1 full JOIN grume_loca g2 ON g1.n_b_exp=g2.n_b_exp AND
g1.ano_b_exp=g2.ano_b_exp AND g1.essence=g2.essence AND g1.n_abat=g2.n_abat AND
g1.volume_sa_def=g2.volume_sa_def
GROUP BY ano_b_exp, n_b_exp, essence
La ou ne je ne suis plus sûr c'est ici, quel comment déclarer
FROM
grume g1 full JOIN grume_loca g2 ON g1.n_b_exp=g2.n_b_exp AND
g1.ano_b_exp=g2.ano_b_exp AND g1.essence=g2.essence AND g1.n_abat=g2.n_abat AND
g1.volume_sa_def=g2.volume_sa_def
merci a vous tous