Django model field name “check” raises SystemCheckError

问题

The Django docs state there are only two restrictions on model field names

A field name cannot be a Python reserved word
A field name cannot contain more than one underscore in a row

However, given the following example, it doesn't look like I can use the field name check as a ForeignKey.

class Check(models.Model):

    name = models.CharField(max_length=100)

class MyModel(models.Model):

    # this works fine
    #check = models.BooleanField()

    # this breaks
    check = models.ForeignKey(Check, on_delete=models.PROTECT, related_name='+')

Here's the error:

$ python manage.py check
SystemCheckError: System check identified some issues:

ERRORS:
myapp.MyModel: (models.E020) The 'MyModel.check()' class method is currently overridden by <django.db.models.fields.related_descriptors.ForwardManyToOneDescriptor object at 0x03A818D0>

Are the docs wrong, or am I doing something wrong?

Edit: forgot to mention this project is using Python 2 and Django 1.11

回答1:

I found System check framework in django docs (https://docs.djangoproject.com/en/2.2/ref/checks/#system-check-framework)

Your check field called during django's system checks so raised SystemCheckError.

It occurred in django's Basecommand (https://github.com/django/django/blob/1e87c9fe71703fab23039aa63fafe4f6aac98bbc/django/core/management/base.py#L148)

1. ``django-admin`` or ``manage.py`` loads the command class
   and calls its ``run_from_argv()`` method.
2. The ``run_from_argv()`` method calls ``create_parser()`` to get
   an ``ArgumentParser`` for the arguments, parses them, performs
   any environment changes requested by options like
   ``pythonpath``, and then calls the ``execute()`` method,
   passing the parsed arguments.
3. The ``execute()`` method attempts to carry out the command by
   calling the ``handle()`` method with the parsed arguments; any
   output produced by ``handle()`` will be printed to standard
   output and, if the command is intended to produce a block of
   SQL statements, will be wrapped in ``BEGIN`` and ``COMMIT``.
4. If ``handle()`` or ``execute()`` raised any exception (e.g.
   ``CommandError``), ``run_from_argv()`` will  instead print an error
   message to ``stderr``.

来源：https://stackoverflow.com/questions/54681167/django-model-field-name-check-raises-systemcheckerror

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