ERROR: XXX.App: (models.E015) ‘ordering’ refers to the nonexistent field, related field, or lookup ‘XXX’.

Hey readers,
I wanted to share with you an issue that I ran into today and how I solved it.

Problem:

I’m working on creating a new model in my django app. All the fields were created, and I wanted my app to sort the model by the ‘name’ field. Provided below is my code:

from django.db import models
from django.urls import reverse # Used to generate URLs by reversing the URL patterns
import uuid # Required for unique book instances
class Stock(models.Model):
      """Model representing a user's selected stock
      Args:
            models (_type_): _description_
      """
      id = models.UUIDField(primary_key=True, default=uuid.uuid4),
      name = models.TextField('Stock Name', max_length=1000, null=False),
      symbol = models.TextField('Ticker Symbol', max_length=100, null=False),
      tags = models.TextField('Search Tags', max_length=1000, help_text="Enter additional keywords to use in the search ('#XBox', 'IOS')"),
      active=models.BooleanField('Activate or Deactivate', default=True, help_text="Check to activate the stock or uncheck to deactivate the stock."),
      def __str__(self):
          return f'{self.name} - {self.symbol}'
      class Meta:
            ordering=['-name']
      def get_absolute_url(self):
          """Returns the URL to access a detail record for this stock."""
          return reverse('stock-detail', args=[str(self.id)])
from django.db import models
from django.urls import reverse # Used to generate URLs by reversing the URL patterns
import uuid # Required for unique book instances

class Stock(models.Model):

      """Model representing a user's selected stock

      Args:
            models (_type_): _description_
      """
      id = models.UUIDField(primary_key=True, default=uuid.uuid4),
      name = models.TextField('Stock Name', max_length=1000, null=False),
      symbol = models.TextField('Ticker Symbol', max_length=100, null=False),
      tags = models.TextField('Search Tags', max_length=1000, help_text="Enter additional keywords to use in the search ('#XBox', 'IOS')"),
      active=models.BooleanField('Activate or Deactivate', default=True, help_text="Check to activate the stock or uncheck to deactivate the stock."),

      def __str__(self):
          return f'{self.name} - {self.symbol}'

      class Meta:
            ordering=['-name']

      def get_absolute_url(self):
          """Returns the URL to access a detail record for this stock."""
          return reverse('stock-detail', args=[str(self.id)])
from django.db import models
from django.urls import reverse # Used to generate URLs by reversing the URL patterns
import uuid # Required for unique book instances

class Stock(models.Model):

      """Model representing a user's selected stock

      Args:
            models (_type_): _description_
      """
      id = models.UUIDField(primary_key=True, default=uuid.uuid4),
      name = models.TextField('Stock Name', max_length=1000, null=False),
      symbol = models.TextField('Ticker Symbol', max_length=100, null=False),
      tags = models.TextField('Search Tags', max_length=1000, help_text="Enter additional keywords to use in the search ('#XBox', 'IOS')"),
      active=models.BooleanField('Activate or Deactivate', default=True, help_text="Check to activate the stock or uncheck to deactivate the stock."),

      def __str__(self):
          return f'{self.name} - {self.symbol}'

      class Meta:
            ordering=['-name']

      def get_absolute_url(self):
          """Returns the URL to access a detail record for this stock."""
          return reverse('stock-detail', args=[str(self.id)])

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Once I was done with developing the model, I saved my changes and started the migration process.

In my terminal I typed in the following command:

python3 manage.py makemigrations

Once I hit enter I got the following error:

_SystemCheckError: System check identified some issues:

ERRORS:
StockTwitterApp.Stock: (models.E015) ‘ordering’ refers to the nonexistent field, related field, or lookup ‘name’._

Next I went to google to see if anyone had experience a similar issue. I went through a couple of stackoverflow results and nothing panned out.

Next I decided to compare my code with the tutorial’s example I was using to see if I had missed anything or added anything additional that was not needed. And then I found it…..

Solution:

It was was the commas ‘,’ . The commas at the end of each field definition (see below):

id = models.UUIDField(primary_key=True, default=uuid.uuid4)->,<-
id = models.UUIDField(primary_key=True, default=uuid.uuid4)->,<-
id = models.UUIDField(primary_key=True, default=uuid.uuid4)->,<-

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Once I had removed the commas from the end of each field definition, saved my changes, and then reran the makemigrations command (python3 manage.py makemigrations)….boom!!! The creation of the migration was a success.

What did I learn:

Do not put commas where they do not belong 🙂

I hope this was helpful.

Please feel free to leave any feedback and\or questions you may have.

Thanks for reading and have a wonderful day.

原文链接：ERROR: XXX.App: (models.E015) ‘ordering’ refers to the nonexistent field, related field, or lookup ‘XXX’.