При выполнении manage.py makemigrations появляется ошибка о том, что таблица (на которую надо сделать миграцию) не существует:
Список вызовов
Traceback (most recent call last):
File "manage.py", line 22, in <module>
execute_from_command_line(sys.argv)
File "D:enviropmentsNewElionlibsite-packagesdjangocoremanagement__init__.py", line 367, in execute_from_command_line
utility.execute()
File "D:enviropmentsNewElionlibsite-packagesdjangocoremanagement__init__.py", line 359, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "D:enviropmentsNewElionlibsite-packagesdjangocoremanagementbase.py", line 294, in run_from_argv
self.execute(*args, **cmd_options)
File "D:enviropmentsNewElionlibsite-packagesdjangocoremanagementbase.py", line 342, in execute
self.check()
File "D:enviropmentsNewElionlibsite-packagesdjangocoremanagementbase.py", line 374, in check
include_deployment_checks=include_deployment_checks,
File "D:enviropmentsNewElionlibsite-packagesdjangocoremanagementbase.py", line 361, in _run_checks
return checks.run_checks(**kwargs)
File "D:enviropmentsNewElionlibsite-packagesdjangocorechecksregistry.py", line 81, in run_checks
new_errors = check(app_configs=app_configs)
File "D:enviropmentsNewElionlibsite-packagesdjangocorechecksurls.py", line 14, in check_url_config
return check_resolver(resolver)
File "D:enviropmentsNewElionlibsite-packagesdjangocorechecksurls.py", line 24, in check_resolver
for pattern in resolver.url_patterns:
File "D:enviropmentsNewElionlibsite-packagesdjangoutilsfunctional.py", line 35, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "D:enviropmentsNewElionlibsite-packagesdjangourlsresolvers.py", line 313, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "D:enviropmentsNewElionlibsite-packagesdjangoutilsfunctional.py", line 35, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "D:enviropmentsNewElionlibsite-packagesdjangourlsresolvers.py", line 306, in urlconf_module
return import_module(self.urlconf_name)
File "D:Python27Libimportlib__init__.py", line 37, in import_module
__import__(name)
File "D:YandexDiskWORK!Projects DjangotestElionElionurls.py", line 5, in <module>
from about import views as about_views
File "D:YandexDiskWORK!Projects DjangotestElionaboutviews.py", line 6, in <module>
from .forms import ContactMessageForm, SubmitApplication
File "D:YandexDiskWORK!Projects DjangotestElionaboutforms.py", line 42, in <module>
class SubmitApplication(forms.Form):
File "D:YandexDiskWORK!Projects DjangotestElionaboutforms.py", line 43, in SubmitApplication
regions = [(obj.id, obj.region) for obj in AreasWork.objects.all()]
File "D:enviropmentsNewElionlibsite-packagesdjangodbmodelsquery.py", line 256, in __iter__
self._fetch_all()
File "D:enviropmentsNewElionlibsite-packagesdjangodbmodelsquery.py", line 1087, in _fetch_all
self._result_cache = list(self.iterator())
File "D:enviropmentsNewElionlibsite-packagesdjangodbmodelsquery.py", line 54, in __iter__
results = compiler.execute_sql()
File "D:enviropmentsNewElionlibsite-packagesdjangodbmodelssqlcompiler.py", line 835, in execute_sql
cursor.execute(sql, params)
File "D:enviropmentsNewElionlibsite-packagesdjangodbbackendsutils.py", line 79, in execute
return super(CursorDebugWrapper, self).execute(sql, params)
File "D:enviropmentsNewElionlibsite-packagesdjangodbbackendsutils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "D:enviropmentsNewElionlibsite-packagesdjangodbutils.py", line 94, in __exit__
six.reraise(dj_exc_type, dj_exc_value, traceback)
File "D:enviropmentsNewElionlibsite-packagesdjangodbbackendsutils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "D:enviropmentsNewElionlibsite-packagesdjangodbbackendssqlite3base.py", line 337, in execute
return Database.Cursor.execute(self, query, params)
django.db.utils.OperationalError: no such table: AreasWorkВ этом списке вызовов показано, что вызывается forms.py этого приложения в том месте где есть обращение к данной таблице:
# Elionaboutforms.py:
class SubmitApplication(forms.Form):
regions = [(obj.id, obj.region) for obj in AreasWork.objects.all()] # Ошибка в этой строке
choice_region = [(None, 'Выберите город')] + regions + [('0', 'Другой')]
region = forms.ChoiceField(label='Область', choices=choice_region,
widget=forms.Select(attrs={'class': 'form-control'}))
............
Если в этом месте убрать обращение к БД, то ошибок больше никаких не появляется. Даже после выполнения manage.py migrate и в forms.py вернуть код обратно, то всё будет работать нормально, без ошибок.
Также, я нашёл, что у кого-то была аналогичная проблема и тоже ошибка в файле forms.py при обращении к БД.
Понятно, что для решения проблемы, надо тупо убрать обращение к БД в форме, но мне интересно, почему вообще такое происходит и что я делаю не правильно?
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rproffitt
2,383
«Nothing to see here.»
Moderator
5 Years Ago
Edited
5 Years Ago
by rproffitt because:
Spelling
cereal
1,524
Nearly a Senior Poster
Featured Poster
5 Years Ago
Hi!
In addition to previous suggestion: if the path is wrong or does not have write permissions Python would return:
sqlite3.OperationalError: unable to open database fileInstead you get:
sqlite3.OperationalError: no such table: AirportsWhich can be generated if:
- the database file name is wrong due, for example, to the case: linux is case sensitive, Mac OS no (at least not by default)
- the database file or the parent directory is read-only, so you have to change the permissions
- the table does not exists
In the first case connect() will create the database file, but this obviously won’t have the Airports table.
In the first case this:
for row in cur.execute('''SELECT "Hello"'''):
print rowwill run successfully, it will run successfully also if the file is read-only, but it will fail if there are permission issues with the parent directory. The error, however, will be related to the database file, not to the table.
Edited
5 Years Ago
by cereal
5 Years Ago
rproffitt, well — capitalization may be important in postgress but not in sqlite. In this case our vendor spelled table «Airports» as «Airports» but in a terminal «aIrPoRtS» will do just fine if one is so inclined.
cereal, the path is correct. To be sure I copied it from a file manager. The permissions of directory and file are set correctly as well. The table exists — I’ve been working with it in a terminal while trying to make this python script.
Meanwhile I did some editing and the new version works fine:
#!/usr/bin/python
import sqlite3
datafile = 'XZ704.DB'
datadir = '/full_path_to/SQLITE_FILES/'
datadir = '../SQLITE_FILES/'
db = datadir+datafile
conn = sqlite3.connect(db)
conn.text_factory = sqlite3.OptimizedUnicode
cur = conn.cursor()
for row in cur.execute('SELECT Ident FROM Airports'):
print row
conn.close()Why overwriting the the first content of «datadir» made a difference…???
conn.text_factory = sqlite3.OptimizedUnicode was inserted after the script started working.
For now I consider my problem solved — but I’m still puzzled.
Thanks!
rproffitt
2,383
«Nothing to see here.»
Moderator
5 Years Ago
Why overwriting the the first content of «datadir» made a difference…?
Sounds like file permissions or rights issues to me. Your app runs as some user and the overwrite creates the file with the rights of the app and its context.
I find this most often happens under Windows. Linux, not so much. What was the host OS?
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Hello Miguel, I’ve finished your book and tried to build a «notebook» project without the help of the book. «Notebook» is a simplified flasky, no User, no Role, no Migrate, No Manage, just Post.
I thought it would be easy, and everything went well until I added these two lines in views.py:
posts = Post.query.order_by(Post.timestamp.desc()).all() return render_template('index.html', current_time = datetime.utcnow(), form = form, posts = posts)
I got the following error:
sqlalchemy.exc.OperationalError: (OperationalError) no such table
I read issue #18, but still can’t solve my problem(I didn’t use manager to modify the command line).
Could you please tell me what’s wrong with it?
Thank you !!
Here’s my code:
run.py
# -*- coding:utf-8 -*-
from app import create_app
app = create_app()
if __name__ == '__main__':
app.run(debug = True)
init.py
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_moment import Moment
from flask_bootstrap import Bootstrap
moment = Moment ()
bootstrap = Bootstrap()
db = SQLAlchemy()
def create_app():
app = Flask(__name__)
moment.init_app(app)
bootstrap.init_app(app)
app.secret_key = 'SECRET_KEY'
db.init_app(app)
with app.app_context():
db.create_all()
from .main import main as main_blueprint
app.register_blueprint(main_blueprint)
return app
views.py
from flask import render_template, redirect, url_for, session
from datetime import datetime
from . import main
from app.forms import PostForm
from flask_login import current_user
from ..models import Post
@main.route('/', methods = ['GET', 'POST'])
def index():
form = PostForm()
if form.validate_on_submit():
post = Post(body = form.body.data)
db.session.add(post)
db.session.commit()
return redirect(url_for('.index'))
posts = Post.query.order_by(Post.timestamp.desc()).all()
return render_template('index.html', current_time = datetime.utcnow(), form = form, posts = posts)
@main.errorhandler(404)
def page_not_found(e):
return render_template('404.html'), 404