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How to fix: Django error: no such table: main.classroom_student__old

I am following this tutorial for learning how to create a Django (v2.0.1) app with multiple user types (teachers and students in this case). I cloned the associated code from the Github Repository, migrated the pre-made migrations and ran the site on localhost using:
python3 manage.py migrate
python3 manage.py runserver
The site works almost perfectly (Teacher sign up, login, quiz creation, and student log in are all in order). However, the student Signup fails with the following error:
OperationalError at /accounts/signup/student/
no such table: main.classroom_student__old
With the traceback pointing eventually to the file
django_school/classroom/forms.py, line 39:
student.interests.add(*self.cleaned_data.get('interests'))
That line comes from the definition of the following class in that forms.py file:
class StudentSignUpForm(UserCreationForm):
interests = forms.ModelMultipleChoiceField(
queryset=Subject.objects.all(),
widget=forms.CheckboxSelectMultiple,
required=True
)
class Meta(UserCreationForm.Meta):
model = User
#transaction.atomic
def save(self):
user = super().save(commit=False)
user.is_student = True
user.save()
student = Student.objects.create(user=user)
student.interests.add(*self.cleaned_data.get('interests'))
return user
What I have tried:
Following answers to the many similar questions on this site, I assumed it was a migration issue so I tried running:
python manage.py migrate --run-syncdb
Operations to perform:
Synchronize unmigrated apps: crispy_forms, humanize, messages, staticfiles
Apply all migrations: auth, classroom, contenttypes, sessions
Synchronizing apps without migrations:
Creating tables...
Running deferred SQL...
Running migrations:
No migrations to apply.
But the error persisted. I then deleted db.sqlite3 as well as all migration files associated with the app classroom. I then ran python3 manage.py makemigrations followed by python manage.py migrate --run-syncdb, again to no avail.
This makes me think that this is an issue with the way the code is adding "interests" to the "student" user object. Indeed, commenting out the line in question stops the error and creates the new student user, however this has the obvious issue that the student has no interests stored.
Running python manage.py sqlmigrate classroom 0001 shows:
...
-- Add field quizzes to student
--
ALTER TABLE "classroom_student" RENAME TO "classroom_student__old";
CREATE TABLE "classroom_student" ("user_id" integer NOT NULL PRIMARY KEY REFERENCES "classroom_user" ("id") DEFERRABLE INITIALLY DEFERRED);
INSERT INTO "classroom_student" ("user_id") SELECT "user_id" FROM "classroom_student__old";
DROP TABLE "classroom_student__old";
COMMIT;
So the database in question (classroom_student__old) is getting created and deleted when another attribute "quizzes" is added to the student user object. Could this be creating the issue?

Instead of downgrading to sqlite 3.24.0, another solution for making the tutorial you listed run successfully is to change the requirements.txt file's django version to 2.2.7 before running the "pip install -r requirements.txt" command.
So, your requirements.txt file for this project would be:
Django==2.2.7
django-crispy-forms==1.7.0
pytz==2017.3

Just to close the question, #SwapnilBhate had the correct answer; it was the sqlite version 3.26.0. After downgrading to 3.24.0, deleting the directory, and reinstalling, everything works perfectly.

1.0) First try:
python manage.py migrate YOURAPPNAME --fake
2.0) If it still doesn't working delete all the migrations files inside your app migrations(except init.py) and pycache folder. After that run makemigrations and migrate.

Use django==2.2.7
then python manage.py migrate,
and finally python runserver

Relation does not exist error in Django

I know there are many questions about this problem, I looked through the solutions and unfortunately none of them worked for me.
I created a new app called "usermanagement", and added a model to the app. After adding the model I added usermanagement to INSTALLED_APPS in settings. Then I ran python manage.py makemigrations, and python manage.py migrate. This all worked fine! I also did try running the migrations with the app-name.
The problems start when I try to add a new instance of the model to the database in the Python-Django shell, by using:
>>>a = ClubOfficial(name="randomName", email="randomemail#random.com")
>>>a.save()
I get the following error:
django.db.utils.ProgrammingError: relation
"usermanagement_clubofficial" does not exist
LINE 1: INSERT INTO "usermanagement_clubofficial" ("name", "email") ...
Below is the model code:
class ClubOfficial(models.Model):
name = models.CharField(max_length=254)
email = models.EmailField(max_length=254)
If it helps, I use postgresql, and have tried restarting the server. The other apps in the program also work perfectly fine, it is just usermanagemenet that has this problem.
Does anyone know what could be going wrong?
Thank you for your time!
Note: I created a new app now with a different name, copy-pasted things from usermanagement and everything worked fine. I think the problem might be that before there was an app named usermanagement which was deleted, before I created it again. Maybe that messed up the database somehow.

TL;DR: Make sure your app's migrations folder has an __init__.py file. If it isn't there, create it again as an empty file.
I ran into this. In my case I had a previously working django app, not yet moved to production, so I deleted everything in my app's migrations folder, then using django extensions I wiped the postgresql database and cached files with:
./manage.py clear_cache
./manage.py clean_pyc
./manage.py reset_schema
./manage.py reset_db
# then deleted all files (including __init__.py) from my app's migrations folder.
I verified that my postgresql database had no tables. I then ran:
./manage.py makemigrations
./manage.py migrate
Which gave the output:
No changes detected
./manage.py migrate
Operations to perform:
Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
(about 11 more lines of output here which are similar)
It is notable that my model's names where nowhere in the migration. I printed the tables in my postgresql database and the Widget and Section tables were both missing. Running the app gave me this error (I substituted 'app' and 'model' for their real names):
ProgrammingError at /my_path
relation "app_model" does not exist
LINE 1: ..."."my_field", "app_model"."my_field" FROM "appname...
So the tables for the models were not being created in the database. My app's migrations folder was also completely empty. The solution was to just add an empty __init__.py to my app's migrations folder, and after that running makemigrations was able to create and save the migration file in the folder. This could then be executed with migrate. You can test this for yourself by running makemigrations with and without the __init__.py in the migrations/ folder.
This solution was not mine but one given by user Ljubitel on another post but it was not the accepted answer there, but the accepted answer didn't work for me so I wrote this solution here to hopefully help others.

I had this same problem, but all I had to do was run
$ python manage.py makemigrations
and
$ python manage.py migrate

In case you have deleted your migration folder.
Create a folder called migration in whatever app name you have created and then create a file in the migration folder called __init__.py

In my case I was pointing to a different databases between my local server and the production server. The database that the production server was pointing to was a few versions behind, so the server could not locate the relation. If your issue were localized to one environment, check the configs first.

Another method to fix relation does not exist error
Create same table in db(postgre, mysql) using sql query tool
now comment your model in models.py and admin.py
run migration using :
python manage.py makemigrations app_name
python manage.py migrate
now uncomment and run migrations command again
I encountered same issue and fixed using following method, I am using postgres(pgadmin 4).

Django : Table doesn't exist

I dropped some table related to an app. and again tried the syncdb command
python manage.py syncdb
It shows error like
django.db.utils.ProgrammingError: (1146, "Table 'someapp.feed' doesn't exist")
models.py
class feed(models.Model):
user = models.ForeignKey(User,null=True,blank=True)
feed_text = models.CharField(max_length=2000)
date = models.CharField(max_length=30)
upvote = models.IntegerField(default=0)
downvote = models.IntegerField(default=0)
def __str__(self):
return feed.content
What I can do to get the tables for that app ?

drop tables (you already did),
comment-out the model in model.py,
and ..
if django version >= 1.7:
python manage.py makemigrations
python manage.py migrate --fake
else
python manage.py schemamigration someapp --auto
python manage.py migrate someapp --fake
comment-in your model in models.py
go to step 3. BUT this time without --fake

For those that may still be having trouble (like me), try this out:
Comment out all the URL's in the main app's urls.py
Then go ahead and run migrations:
$ ./manage.py makemigrations
$ ./manage.py migrate
The problem was alleviated by removing the ()'s
solved_time = models.DateTimeField('solved time', default=timezone.now())
to
solved_time = models.DateTimeField('solved time', default=timezone.now)
I got this answer from reddit

What solved my problem in situation when manage.py setmigration and then migrate to the SQL database is not working properly did is following:
Run command : python manage.py migrate --fake MyApp zero
After that: python manage.py migrate MyApp
And the problem that rises with connections.py and and after running correctly the migration command is solved! At least for me.
I'm using Python (3.x), MySQL DB, Django (3.x), and I was in situation when I needed after some time of successfully creating tables in my database, that some error regarding connections.py raises. But, above commands helped. I hope they will help all those who are having these type of problems.

I just ran migrations with the name of the app attached, for all the apps I had provisioned and that worked.
e.g. python3 manage.py makemigrations my_custom_app
After running for all of them I ran a migrate command to seal the deal.
python3 manage.py migrate. That was it. I'm still wondering why django behaves this way sometimes though.

none of the above solutions worked for me, I finally solved by
sudo systemctl stop mysql.service
sudo apt-get purge mysql-server
sudo apt-get install mysql-server
sudo systemctl stop mysql.service
In my case the code that I pulled had managed = False and I wanted the tables to be maintained by Django.
But when I did makemigrations the custom tables were not being detected or I was getting the error that the app_name.Table_name does not exist
I tried the following:
delete all the migration files inside the migrations folder (except init.py file) and then makemigrations then finally migrate
above 2 answers
this
PS: This solution is only feasible if backup is present or data is not important or you are just started creating the tables, as purging mysql will lead to loss of data

This is linked to the migration data in the scripts inside the project not matching with the migration scripts in the database as far as I could tell.
I solved this by the following steps :
Delete all the migration scripts under migration folder except __ini__
Make sure that the model.py contains the same structure as the table in the database and managed=True
Remove all Django Created tables like auth_user,... etc
Run the following code
$ ./manage.py makemigrations
$ ./manage.py migrate
This will create the migration scripts again and will apply it to your database.

I had this issue where I was playing with same database structure in production vs development. While dropping and recreating tables will probably resolve the issue, its worth checking your database itself and see if the model is actually correct. For myself I created the development database incorrectly with the table names all in lowercase while in production the first letter of tables were capitalized. I used the python manage.py inspectdb command on production db, and compared it to the model and realized that in the model it was trying to insert data to table 'test' instead of 'Test' for example. Hope that helps some of you in future.

I had a similar issue.
I had another python (with a class) file which need access to DB.
For some reasons, when running 'makemigrations' this file was processed (I guess this is linked to some import chains).
In this class, I had a method containing a default arg method(defaultModel=Model.get_default()) in the signature which was accessing to the default object in the DB (static method included in the Model class).
A the import time, this default arg was evaluated and as the table is not populated yet, it gives this error.
So I just set None for the default args and asks for the default model object inside the method. This solved the issue.

I have to face same issue and there are a couple of approaches, but the one I think is the most probable one.
Maybe you are loading views or queries to database but you haven´t granted enough time for Django to migrate the models to DB. That's why the "table doesn't exist".
Make sure you use this sort of initialization in you view's code:
Class RegisterForm(forms.Form):
def __init__(self, *args, **kwargs):
super(RegisterForm, self).__init__(*args, **kwargs)
A second approach is you clean previous migrations, delete the database and start over the migration process.

I tried all of the above tricks and never worked for me.
I commented on all imports and URLs that called a particular Table

In this solution, your data will be removed. I removed the app and created the app again. I copied the app folder somewhere and delete the app folder from my project. I commented on all lines in urls.py and files similar views.py and admin.py that use this app. also app name in settings.py.
In mysql:
truncate django_migrations;
truncate django_admin_log;
Do this for all models in your app and change n.
n is app id.
delete from auth_permission where content_type_id=n
delete from django_content_type where app_label='appname'
python manage.py startapp your_app_name
Then uncomment previous lines and restore files and run
python manage.py makemigrations
python manage.pt migrate

I faced the same problem, some of the above mentioned answers seemed not to work for me, but here's a simple 4 step solution:
1) Delete the migrations files below __init__.py (don't delete __init__.py) in your specific app.
2) python manage.py makemigrations AppName
3) python manage.py migrate --fake AppName zero
4) python manage.py migrate AppName
Hope these works for you.

I faced the same issue earlier when I accidentally deleted my migrations folder in an app. I was able to fix it by running manual makemigrations for that specific app.
Here's the fix for Windows,
py manage.py makemigrations <your_app_name>
py manage.py migrate
For other OS you need to replace py with python3 or python
I hope this helped fix your issue!

if the python manage.py migrate still doesn't work I mean when you do this it nothing do anything you can delete the app's migrations from django_migrations table after then do
python manage.py migrate

Issues with creating table via migration

I have created a model and when I try to create the table via migration using python manage.py migrate app_name and in response I get
- Nothing to migrate.
- Loading initial data for app_name.
Installed 3 object(s) from 1 fixture(s)
But the table is not created , its a simple process but I don't know why the table is not created. The db used is postgresql and I have also used syncdb but doesn't work .

It seems you haven't created any migrations. You need to create them, before they can be run.
For app's initial first migration you run:
./manage.py schemamigration your_app --initial
For following migrations you run (provided you want to create an automatic migration):
./manage.py schemamigration your_app --auto
You can see more examples in the tutorial.

Django & South: Adding new field but DatabaseError occurs "table already exists"

In trying to add a new field to a preexisting Model/table, I get a DatabaseError with 'table already exists.' I have run migrations before this one so I am a bit puzzled why adding a new field would pop up this error.
Commands executed:
python manage.py schemamigration app --auto
python manage.py migrate app
Previous SO questions like this were answered with faking a migration.
python manage.py migrate app --fake
python manage.py migrate app
The problem that arises from this is that the column is not created. So when you runserver, you will see a DatabaseError 'no such column'.
As far as my model, I am only adding a CharField.
Thanks in advance for your help-

You need to do schemamigration app --initial first without your new field, then migrate app --fake 0001 (or whichever migration number it returned) to set the south database to that state (tables already created).
Add your new field, then run schemamigration myapp --auto, then migrate.

I commented out the field, ran schemamigration, then migrate. Uncommented out the field, ran schemamigration, then migrate and it worked. Not sure what I was doing wrong.

This happens when you doing something on migration and did not let south knows about it.
If you looking at the south_* table in the database, you will find-out south keeps logs about db migrations in the database. The common way is to faking the migration.
There is a fake argument for the South.
here you can find out what is all about:
http://south.readthedocs.org/en/latest/commands.html#options