python - 包括其他字段作为外键的选择，Django

Question

我有两个模型如下:

class FlightSchedule(models.Model):
    tail_number = models.ForeignKey(TailNumber, null=False, blank=False)
    flight_number = models.CharField(max_length=30, null=False, blank=False)
    flight_group_code = models.ForeignKey(FlightGroup, null=False, blank=False)
    origin_port_code = models.ForeignKey(Port, null=False, related_name="Origin", blank=False)
    destination_port_code = models.ForeignKey(Port, null=False, related_name="Destination", blank=False)
    flight_departure_time = models.TimeField()
    start_date = models.DateField()
    end_date = models.DateField()

    def __unicode__(self):
        return u'%s' % self.flight_number

    class Meta:
        verbose_name_plural = "flights Schedule"


class PosFlightSchedule(models.Model):
    tail_number = models.ForeignKey(TailNumber, null=False, blank=False)
    pos_flight_number = models.ForeignKey(FlightSchedule, max_length=30, null=False, blank=False,
                                      related_name='pos_flight_number')
    pos_flight_departure_time = models.ForeignKey(FlightSchedule, max_length=30,
                                              related_name='pos_flight_departure_time')
    pos_route_id = models.ForeignKey(FlightScheduleDetail, null=False, blank=False, related_name='pos_route_id')
    pos_flight_date = models.ForeignKey(FlightScheduleDetail, null=False, blank=False, related_name='pos_flight_date')
    pax_count = models.IntegerField(null=True)

    def __unicode__(self):
        return u'%s' % self.pos_flight_number

    class Meta:
        verbose_name_plural = "Flights Schedule"

对于 pos_flight_departure_time ，我需要从 FlightSchedule 类的 flight_departure_time 中进行选择。但是我在下拉列表中得到了 flight_number 值。我必须更改什么才能获得 flight_departure_time 值？这些类来自单个 django 项目中的不同应用程序。所以他们有两个管理文件。

Answer 1

不，你实际上并不需要它。您的第二个模型中只需要一个外键到 FlightScheduleDetail 并且您只需要一个外键到 FlightSchedule

class PosFlightSchedule(models.Model):
    tail_number = models.ForeignKey(TailNumber, null=False, blank=False)
    flight = models.ForeignKey(FlightSchedule, null=False, blank=False,related_name='pos_flight_number')
                                              related_name='pos_flight_departure_time')
    pos_route_id = models.ForeignKey(FlightScheduleDetail, null=False, blank=False, related_name='pos_route_id')
            pax_count = models.IntegerField(null=True)

    def __unicode__(self):
        return u'%s' % self.pos_flight_number

    class Meta:
        verbose_name_plural = "Flights Schedule"

然后在第一个模型中声明的所有字段自动可用于 PosFlightSchedule

例如你可以这样做

p = PosFlightSchedule.objects.all()[0]
print (p.flight.flight_number)
print (p.flight.pos_flight_departure_time)

等

这是正确的做法。