How to insert default value in database table when user account is created in Django?

问题

I am using postgre database have 10 channel in my database. This is my models with channelId and userId as foreign key:

class Count(models.Model):
    userId = models.ForeignKey(User, on_delete=models.CASCADE)
    channelId = models.ForeignKey(News_Channel, on_delete=models.CASCADE)
    rate = models.PositiveIntegerField(default=0)

    def __str__(self):
        return self.channelId.name

    class Meta:
        ordering = ["-id"]

I want when a user account is created then 3 row inserted in the table for all 3 channelId and rate value set to 0. suppsose a user sign up and get userIid 99 then 3 rows inserted in the table as

userId channelId rate
99         1      0
99         2      0
99         3      0

What could be the possible solution.

回答1:

There are 2 possible solutions:

1. You can use signals. Create a post_save signal for your AUTH_USER_MODEL. It is usually used to execute some logic just after a model’s save() method is called. In that signal function write logic for creating Count for all channels and rate. You can get id for ATUTH_USER_MODEL from post_signal.

   Refer https://docs.djangoproject.com/en/2.2/topics/signals/

2. Create a logic for registering user for your AUTH_USER_MODEL and after user creation, create Count for all channels and rate.

来源：https://stackoverflow.com/questions/56303797/how-to-insert-default-value-in-database-table-when-user-account-is-created-in-dj