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How to deal with `Migration is applied before its dependency`

I have been assigned the task to work on project involving react UI and django backend. There are two versions of this app:
older version which runs on older versions of react and python (v2)
newer version which runs on newer versions of react and python (v3)
I have been tasked to move some functionality from older version to newer version and test it with postgres database dump from a live environment running older version. The challenge could be differences in the database schema of newer and older versions. (But, most possibly there wont be much differences if some minor ones.)
So I proceeded to take the database dump, attached it to the database running on my laptop and specified its name in my django's settings.ini. But when I started my django app, it gave me error
You have 7 unapplied migration(s). Your project may not work properly until you apply the migrations for app(s): admin, auth, lab, otherlabs. Run 'python manage.py migrate' to apply them.
When I ran python manage.py migrate, it gave me an error:
Migration abc.0001_initial is applied before its dependency auth.0011_xyz on database 'default'.
So, I deleted record corresponding to abc.0001_initial from django_migrations table and reran python manage.py migrate. Now I got same error for migration of another project def but with the same dependency auth.0011_xyz:
Migration def.0001_initial is applied before its dependency auth.0011_xyz on database 'default'.
Should I proceed with deleting record corresponding to def.0001_initial too? Am afraid that this will continue till I delete all such 0001_initial-suffixed records. There are 35 projects and hence 35 such 0001_initial-suffixed records.
Q1. Is it safe to delete them all and run the migrations? Is deleting all migrations and rerunning them really bad idea if they are schema-only migrations (we use fixtures for importing data)? Or is it simply impossible to do as most of those migrations will fail as tables corresponding to most models are already there in the database (or this wont give any error?), so the only solution remained is to delete migrations record one by one from db till I get no errors. But wont this still give error as I am only deleting migrations record and not actual tables created by migrations? Is there any other approach?
Q2. Are migrations completely safe to "re"-run? I mean if one fails because corresponding table / columns are already there or for some other reasons, will it leave database in consistent state or will it mess up the database?
Q3. Also will it continue to execute rest of the migrations after one fails? OR
Q4. Can / should I execute rest of the migrations if one fails? If yes, do I need to pass some arguments to python manage.py migrate or its default behavior?
Update
I tried removing all migrations from the django_migrations table. And then running python manage.py makemigrations followed by python manage.py migrate. But migration did not complete and terminated with error "relation already exist". So applied fake migration python manage.py migrate --fake. It succeeded (seems that it faked / skipped all migrations as all corresponding tables were present, so it did not create new columns in already existing tables). But then my REST API calls started failing with error in response saying: "column xyz does not exist".
Manually copying data seems impossible since there are 156 tables 🥲
Please let me know if there are any solution to this.

You need to delete the migration row from django_migrations for migration def.0001_initial, then apply migrate auth 0011_xyz to fix the dependency and then you should can to do migrate def 0001_initial --fake to fake the migration and add the row you deleted before to django_migrations.

how to run existing Django project

I'm new with python(don't know anything about it), and also in Django... so question is, what and how, step by step, I need to launch existing Django project which I got from github...
so, what I have done already:
installed python
created virtual environment
run python mange.py migrate, but it showed many errors(and I don't know what to do with it and how to fix them), because I can't even connect to DB(previously I worked with MySQL where I can connect by myself and do selects to check something in DB), but now this project uses SQLite3, and I don't know how I can check this database
run python manage.py runserver and I can see my webapp at localhost...
So, main question is, how to properly launch existing Django project?

Create Django app with no User model - 3.1.3 wants to migrate auth_user?

I've got a Django application which has been happily humming along now for quite some time (2 years or so).
It's on 3.0.10 currently - when I tried to upgrade to 3.1.3, it says there was a migration for the auth application. No worries! Never been an issue before...
I ran python manage.py migrate and got the following error:
"Cannot find the object "auth_user" because it does not exist or you do not have permissions."
Which, I suppose would be true because we do not have a User model at all in this application. There is no auth_user table, that is correct. In other apps we have an AbstractUser that routes to a table named: org_user - but again:
this particular app (and project) do not have any User model associated with them
Obviously this (apparently, now) leads to some issues.
Any thoughts on how to get around this? I thought about removing auth from installed apps and tried that but it led to more issues when trying to runserver.

You can fake a migration using --fake option:
python manage.py migrate --fake auth
python manage.py migrate
But I suspect the error you get could be symptomatic of a project design issue, such as not setting properly settings.AUTH_USER_MODEL

Solution 1 :- Run these commands :-
python manage.py migrate auth
python manage.py migrate
Solution 2 :- Try to copy your Project in another folder and then run migrations.

Uninstalling django-tinymce. Import error when makemigrations

Thanks for taking the time to read this.
I was not happy with TinyMCE extension in django and decided to switch to django-summernote. I first ran
pip uninstall django-tinymce
Removed all mentions of tinymce in the actual project.
Followed the instruction to install django-summernote. Upon completion I decided to run
python manage.py makemigrations
python manage.py migrate
to apply new extension, but get an error:
File "/Users/rasulkireev/Sites/dj-pw/now/migrations/0006_auto_20190703_0134.py", line 4, in <module>
import tinymce.models
ModuleNotFoundError: No module named 'tinymce'
I'm not sure why would Django care about what I did previously since I am simply asking to replace the editor. I can't run python manage.py runserver either.
I can't do anything before fixing this. I beg you guys, please help.
Note: I would ideally want to keep the contents of my current database.
Thanks for taking the time to read this.

Once you have removed all the mentions of tinymce from the models, admins and other files, you need to migrate using a special "flag":
python manage.py makemigrations
python manage.py migrate --fake-initial
I am not to clear on the backend of this method, but it works. You can read more about it the official Django website:
https://docs.djangoproject.com/en/2.2/topics/migrations/
This will make a new initial migration for your app. Now, run python
manage.py migrate --fake-initial, and Django will detect that you have
an initial migration and that the tables it wants to create already
exist, and will mark the migration as already applied. (Without the
migrate --fake-initial flag, the command would error out because the
tables it wants to create already exist.)
Note that this only works given two things:
You have not changed your models since you made their tables. For
migrations to work, you must make the initial migration first and
then make changes, as Django compares changes against migration files, not the database.
You have not manually edited your database - Django won’t be able to detect that your database doesn’t match your models, you’ll just get errors when migrations try to modify those tables.

Python social auth in Django, makemigrations detects no changes

I was following the documentation to get python social auth on my django project
https://python-social-auth.readthedocs.org/en/latest/configuration/django.html
And after adding 'social.apps.django_app.default', to the INSTALLED_APPS in my settings.py I run this:
python manage.py makemigrations
I get this
No changes detected
Shouldn't this command be doing something. Because without this I can't migrate to create the tables that are needed for the auth.
EDIT:
I've also tried this command, and still ended up getting the same result
python manage.py makemigrations main
where 'main' is the name of my app

Today i ran into this problem. The error is in the documentation itself.
You should run $ python manage.py migrate directly. It creates tables in the database.
All the old tutorials used makemigrations, I think it was used in earlier versions of django.

My answer will be cover some basics so one can understand this types of errors easily.
Let me clear some basic terminology about migrations in the latest versions of Django(From 1.7 to under development ones).
In older versions of Django when One has to make changes in Models (Eventually in Database) then One has to use South app to apply changes in Database without affecting older database.
Django developer community has included this south app in and after Django 1.7 and also provided some simple commands to apply migrations.
When one install New app(Above question scenario) or one make changes in existing models and wish to apply changes in database then one has to tell database about what changes they want to make. To do so one has to make migrations and below is the command.
$ python manage.py makemigrations app_name
or If it is initial then no need to specify app_name, it will consider all apps.
This command will generate migrations files which will include instructions for database to make what tables and what are the attributes of that table and what will be the relationships between tables and what are changes in the current tables etc etc.
Now one has to run below command to apply this all changes in database.
$ python manage.py migrate app_name
or If it is initial then no need to specify app_name.
Please shoot any questions If you have any and please take a look at Django's official documentation on migrations for more information.

The possible reason is your project doesn't use any database models of 'social' application yet. Add a URL in your urls.py, link it to 'social' urls.

to Django < 1.8
INSTALLED_APPS ['social.apps.Django_appConfig',]