将其他字段包含为外键Django [英] Include other field as choices to foreign key, Django

问题描述

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 = 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 =航班时刻表
 
 
类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，
相关名称='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 =航班时刻表
  

对于 pos_flight_departure_time ，我需要从 flight_departure_time 从 FlightSchedu le 类。但是在下拉列表中我可以得到 flight_number 值。要获得 flight_departure_time 值，需要更改什么？这些课程来自于单个django项目中的不同应用程序。所以他们有两个管理员文件。

解决方案

不，你实际上不需要。您的第二个模型中只需要一个外键 FlightScheduleDetail ，您只需要一个外键 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 =航班时刻表
  

然后在第一个模型中声明的所有字段自动变为 PosFlightSched可用ule

所以例如你可以做

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

等。

这是正确的方法。

I have two models as follows :

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"

For the pos_flight_departure_time , I need the choices from flight_departure_time from the FlightSchedule class. But I get the flight_number values in the drop down. What do I have to change, to get the flight_departure_time values? The classes are from different apps in a single django project. So they have two admin files.

解决方案

No you don't actually need that. You need only one foreign key in your second model to FlightScheduleDetail and you need just one foreign key to 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"

Then all the fields declared in the first model automatically become available to PosFlightSchedule

So for example you can do

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

etc.

This is the correct way to do it.

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