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Chapitre 5 • Le langage SQL DML
5.31 Rechercher les clients qui, s’ils ont commandé le produit PA60, en ont
commandé plus de 500 unités au total.
Suggestion. Il s’agit d’une relation d’implication.
5.32 A la question : "rechercher les localités dans lesquelles on n’a pas commandé
de produit PA60", quatre utilisateurs proposent les requêtes suivantes.
Indiquer la (ou les) requêtes correctes, et interprétez les autres.
select distinct LOCALITE
from
CLIENT
where NCLI in
(select NCLI
from
COMMANDE
where NCOM in
(select NCOM
from
DETAIL
where NPRO <> 'PA60'))
select distinct LOCALITE
from
CLIENT
where NCLI in
(select NCLI
from
COMMANDE
where NCOM not in
(select NCOM
from
DETAIL
where NPRO = 'PA60'))
select distinct LOCALITE
from
CLIENT
where NCLI not in
(select NCLI
from
COMMANDE
where NCOM in
(select NCOM
from
DETAIL
where NPRO = 'PA60'))
select distinct LOCALITE
from
CLIENT
where LOCALITE not in
(select LOCALITE
from
CLIENT
where NCLI in
(select NCLI
from
COMMANDE
where NCOM in
(select NCOM
from
DETAIL
where NPRO = 'PA60')))