我想要的是:
存储有关人群运行的信息。
我做了什么:
from django.db import models
from django.contrib.auth.models import User
from datetime import timedelta
class Route(models.Model):
name = models.CharField(max_length=50)
class Run(models.Model):
date = models.DateField()
type = models.ForeignKey(Route, on_delete=models.PROTECT)
runners = models.ManyToManyField(User, through='RunnerResult', through_fields=["user", "run"])
class RunnerResult(models.Model):
user = models.ForeignKey(User, on_delete=models.PROTECT)
run = models.ForeignKey('Run', on_delete=models.PROTECT)
result = models.DurationField(default=timedelta())
问题:
当我这样做时makemigrations
,出现以下错误:
SystemCheckError: System check identified some issues:
ERRORS:
run.Run.runners: (fields.E339) 'RunnerResult.run' is not a foreign key to 'User'.
HINT: Did you mean one of the following foreign keys to 'User': user?
run.Run.runners: (fields.E339) 'RunnerResult.user' is not a foreign key to 'Run'.
HINT: Did you mean one of the following foreign keys to 'Run': run?
试图在彼此之间以及其他一些操作之间交换 through_fields 和模型。我开始思考我对 M2M 关系的误解。