try:
    #Connexion à la base MySQL
    if (base1 == "mysql") or (base2 == "mysql"):
        cnx = mysql.connector.connect(user=user_mysql,
                                      password=password_mysql,
                                      host=host_mysql,
                                      database=database_mysql)
    #Connexion à la base MSSQL
    if (base1 == "mssql") or (base2 == "mssql"):
        conn = pymssql.connect(server=host_mssql,
                               user=user_mssql,
                               password=password_mssql,
                               database=database_mssql)
    else:
        print "parametres incorrecte !!"
except IndexError:
    print("manque de parametre !!"
          " il faut saisir les deux SGBD à comparer !!")