drop view Historique_Septembre;

create view Historique_Septembre
(Identifiant_Client,Nom_Client,Septembre_HT,Septembre_TTC)
as select 
f.Identifiant_Client,
f.Nom_Client,
f.Prix_HT,
f.Prix_TTC
from Facture f
	where to_char(f.Date_Commande,'MM')= '09'
	order by f.Identifiant_Client; 