在新应用程序中添加时“django.db.utils.OperationalError: no such table”

Question

I recently added the mycase app to my larger django project but since then I have been getting all kinds of database errors. If any more information would be helpful just reply with a comment, I don't know exactly what would be helpful in this case. Thanks: Traceback:

File "manage.py", line 22, in <module>
    main()
  File "manage.py", line 18, in main
    execute_from_command_line(sys.argv)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/management/__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/management/__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/management/base.py", line 330, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/management/base.py", line 368, in execute
    self.check()
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/management/base.py", line 392, in check
    all_issues = checks.run_checks(
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/checks/registry.py", line 70, in run_checks
    new_errors = check(app_configs=app_configs, databases=databases)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/checks/urls.py", line 40, in check_url_namespaces_unique
    all_namespaces = _load_all_namespaces(resolver)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/core/checks/urls.py", line 57, in _load_all_namespaces
    url_patterns = getattr(resolver, 'url_patterns', [])
  File "/opt/anaconda3/lib/python3.8/site-packages/django/utils/functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/urls/resolvers.py", line 589, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/utils/functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/urls/resolvers.py", line 582, in urlconf_module
    return import_module(self.urlconf_name)
  File "/opt/anaconda3/lib/python3.8/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
  File "<frozen importlib._bootstrap>", line 991, in _find_and_load
  File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 783, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/Users/andrew/Desktop/Projects/purplerobotics/purplerobotics/urls.py", line 23, in <module>
    path('case/', include('mycase.urls'))
  File "/opt/anaconda3/lib/python3.8/site-packages/django/urls/conf.py", line 34, in include
    urlconf_module = import_module(urlconf_module)
  File "/opt/anaconda3/lib/python3.8/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
  File "<frozen importlib._bootstrap>", line 991, in _find_and_load
  File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 783, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/Users/andrew/Desktop/Projects/purplerobotics/mycase/urls.py", line 2, in <module>
    from . import views
  File "/Users/andrew/Desktop/Projects/purplerobotics/mycase/views.py", line 7, in <module>
    class CaseHome(ListView):
  File "/Users/andrew/Desktop/Projects/purplerobotics/mycase/views.py", line 10, in CaseHome
    total_price = CaseItem.objects.all().aggregate(total=Sum(F('Item_Price')*F('Item_Quantity')))['total']
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/models/query.py", line 398, in aggregate
    return query.get_aggregation(self.db, kwargs)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/models/sql/query.py", line 500, in get_aggregation
    result = compiler.execute_sql(SINGLE)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/models/sql/compiler.py", line 1156, in execute_sql
    cursor.execute(sql, params)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/backends/utils.py", line 98, in execute
    return super().execute(sql, params)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/backends/utils.py", line 66, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/backends/utils.py", line 75, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/utils.py", line 90, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/opt/anaconda3/lib/python3.8/site-packages/django/db/backends/sqlite3/base.py", line 413, in execute
    return Database.Cursor.execute(self, query, params)
django.db.utils.OperationalError: no such table: mycase_caseitem

Project Settings File:

from pathlib import Path

DEBUG = True

ALLOWED_HOSTS = []

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'theblog',
    'dashboard',
    'mycase'
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'purplerobotics.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'purplerobotics.wsgi.application'


DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    }
}



AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_L10N = True

USE_TZ = True


STATIC_URL = '/static/'

mycase models.py file

from django.db import models
from django.urls import reverse
# Create your models here.

class CaseItem(models.Model):
    Item_Title = models.CharField(max_length=200)
    Item_Price = models.DecimalField(default=0, max_digits=10, decimal_places=2)
    Item_Quantity = models.DecimalField(default=0, max_digits=10, decimal_places=2)

    def __str__(self):
        return self.Item_Title + ' | ' + str(self.Item_Quantity) + ' * $' + str(self.Item_Price)

    def get_absolute_url(self):
        return reverse('home')

If anything else would be helpful I would be happy to get it.

Answer 1

Once you are done with your model, you have to run migrations - this handles the database processes, in this case the creation of the table. so:

python manage.py makemigrations

and

python manage.py migrate