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django-safedelete 1.3.0 - Cannot migrate

I built an internal app that used django-safedelete. I was working fine for months, until i recently upgraded my distro, and tried to add a field to my model.
I also upgraded my python modules, everything is up-to-date, and no errors during the upgrade.
Now I cannot migrate anymore:
if I "makemigrations" I get an error message "django.db.utils.OperationalError: (1054, "Unknown column 'gestion_ltqmappsetting.deleted_by_cascade' in 'field list'")"
if I add a boolean "deleted_by_cascade" field in my ltqmappsetting table, then the "makemigration" works, but the "migrate" fails with "MySQLdb.OperationalError: (1060, "Duplicate column name 'deleted_by_cascade'")"
I tried removing the field after makemigrations, but the migrate fails with the first error message.
I also tried removing the "migration" operations in the 0087...migration.py file, but it does not have any impact.
Is there anyway to update the migration file between the makemigrations and the migrate commands ?
Thanks a lot for any help on this.
jm

It's a wonder how I can actually look for answers for hours, then post on this site, and a few minutes later, I actually find the answer ...
Anyway.
It looked like I was mistaken on the meaning of the second error message. It failed because a previous migration already create the deleted_by_cascade field in another table, not in the appsetting one.
So the steps to solve my issue where:
migrate migrate 0086 to remove the latest migrations
make sure the DB only had the deleted_by_cascade column in the appsetting table
makemigrations - this creates the 0087 migration to add deleted_by_cascade column in all tables
edit the 0087 migration to not create the new column in the appsetting table
run makemigrations once again - - this creates the 0088 migration to add deleted_by_cascade column in the appsetting table
migrate 0087
migrate --fake 0088
Et voila ...
There was probably something wrong in the safe_delete update.
Hope this can help others.
jm

strange migration from django to postgres DB. How to save an exist data

I have walking on a strange way, but it is result of circumstances.
I had to been generate single models.py from exist postgres DB by inspect_db.
Next I fix some field (was a few problem with keys), and create 2 apps inside this project. So now I have 3 models.py (them are split models.py, whitch was generate by inspect_db). managed = True was added. Classes have same links and datatypes like in the database
Next I wish to integrate this models to exist database. I make migration, I migrate and in the end DB have only system django tables (auth_, django_migrations etc.) None from my classes (although migrate files were create). So I tryied to delete migrations catalogs and repeat makemigrations and migrate, but terminal threw it:
Operations to perform:
Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
No migrations to apply.
(forest-venv) user#user-HP-Z800-Workstation ~/MyProjects/forest-venv/lesoved $ python manage.py runserver 8001
Performing system checks...
If I try make migrates again - no changes. I tryied to delete info about my apps in django_migrations table - no result.
So my questions:
- It is possible to integrate new models into exist database (if names, keyes and formats is ok)?
- Integration is possible by the way where data from exist database is saved after migrations?
- How to return possobillity of make migrations? now it isn't work.

The trick when using an existing database is to make sure you start from a well-defined state: First get Django to the exact same state as your db, and only after that start making changes to your models. So these are the steps:
Check that your database doesn't have a django-migrations table, delete it using SQL if needed. (Note: I'm assuming this db isn't generated by Django to start with and you're creating a fresh django application)
Create your models with inspectdb. If needed, rename the models to have proper CamelCase. If you rename models or fields that would change the table or column name in the db, make sure to set db_table (Meta options of your model) and db_column (as field attribute).
Run manage.py makemigrations. Check the migration files for your models, just to be sure the names match with your db.
For your own apps, run manage.py migrate <app> --fake. This will add the migrations to django-migrations table in your db as if they ran, without actually running them.
Then run manage.py migrate to create the django provided tables (auth, contenttype, session etc...)
Now you are at the state where you can start changing things. If you change the model and run makemigrations it should create a migration just for your changes.

django migrate "No migrations to apply."

I kind of know why when I do migrate it gives me the message of no migrations to apply but I just don't know how to fix it
This is what happens.
I added a new field named update into my model fields.
I did a migration which created a file called 0003_xxxxx.py then I did a migrate now this worked fine.
But then because of some reason, I have to remove the update field from the same model.
So I removed it (more likey commented instead of really delete the code) then I did migration and migrate which removed the field in db. (created 0004_xxxxx.py)
But sigh....some reason I have to add the field back again (this is why I only commented out) but then before I do the migration
I removed the 0003_xxxx.py and 0004_xxxx.py files I wanted to remove those two files because this is actually the same or almost the same config as 0003_xxxx.py so I feel it's pointless having the 0003_xxxx.py and 0004_xxxx.py here...also when I go production, that's just another extra step for python to run.
After I removed those two files, I did the migration which creates another 0003_xxxx.py but when I do migrate it gives me the message of no migrations to apply
I know that by deleting the 0003_xxxx.py and get the original 0003 and 0004 back then do another migration (creates 0005_xxxx.py) then migrate then changes will be made. I know this because I didn't really delete the original 0003 and 0004 I moved it somewhere just in case of this kind of happening.
But why is this though? and is there a way to fix it?
Thanks in advance for any replies

django keep records of current migrations log by table django_migrations in your db.
something like:
The migrations is a chain structure,it's depend on the parent node.By this table django can know which migrations file is executed.
In you case,no migrations to apply because the new create 0003_xxxx.py is record in this table,you can fix it by delete this record in this table.
If you want remove some migration file you need see Squashing migrations.

Or even simply just delete the last migration row from your database you can try the following
First, check which row you want to remove
SELECT * FROM "public"."django_migrations";
Now pick the last id from the above query and execute
DELETE FROM "public"."django_migrations" WHERE "id"=replace with your Id;
run ./manage.py migrate.

just run:
python manage.py run --run-syncdb

How to create a new table using model

So I have this django installation in which there are a bunch of migration scripts. They look like so:
00001_initial.py
00002_blah_blah.py
00003_bleh_bleh.py
Now I know these are "database building" scripts which will take stuff defined in models.py and run them against the db to "create" tables and stuff.
I want to create a new table(so I created its definition in models.py). For this, I have copied another model class and edited its name and fields and it is all fine. Lets call this new model class 'boom'.
My question is now how do I "create" this boom table using the migration script and the boom model?
I am worried that I might accidentally disrupt anything that is already in DB. How do I run the migration to create only boom table? How do I create a migration script specifically for it?
I know that it has something to do with manage.py and running migrate or runmigration (or is it sqlmigrate?...im confused). While creating the boom table, I dont want the database to go boom if you know what I mean :)

First, create a backup of your database. Copy it to your development machine. Try things out on that. That way it doesn't matter if it does go "boom" for some reason.
The first thing to do is
python manage.py showmigrations
This shows all the existing migrations, and it should show that they have been applied with an [X].
Then,
python manage.py makemigrations
Makes a new migration file for your new model (name 00004_...).
Then do
python manage.py migrate
to apply it. To undo it, go back to the state of migrations 00003, with
python manage.py migrate <yourappname> 00003

There are two steps to migrations in Django.
./manage.py makemigrations
will create the migration files that you see - these describe the changes that should be made to the database.
You also need to run
./manage.py migrate
this will apply the migrations and actually run the alter table commands in SQL to change the actual database structure.
Generally adding fields or tables won't affect anything else in the database. Be more careful when altering or deleting existing fields as that can affect your data.
The reason for two steps is so that you can make changes on a dev machine and once happy commit the migration files and release to your production environment. Then you run the migrate command on your production machine to bring the production database to the same state as your dev machine (no need for makemigrations on production assuming that your databases started the same).

My question is now how do I "create" this boom table using the
migration script and the boom model?
./manage.py makemigrations
I am worried that I might accidentally disrupt anything that is
already in DB.
The whole point of migrations, is that it doesn't
I know that it has something to do with manage.py and running migrate
or runmigration
For more information please refer to : https://docs.djangoproject.com/en/1.10/topics/migrations/
And rest assured that your database will not go boom! :-)

I solved it simply, changing the name of the new model to the original name, and then I checked if there is the table in the database, if not, I just create a new table with the old name with just a field like id.
And then clear migrations and create new migrations, migrate and verify table was fixed in DB and has all missing fields.
If it still doesn't work, then change the model name back to a new one.
but when django asks you if you are renaming the model you should say NO to get the old one removed properly and create a new one.
This type of error usually occurs when you delete some table in dB manually, and then the migration history changes in the tables are lost.
But it is not necessary to erase the entire database and start from scratch.

You cannot add a null=False column without a default value

I'm adding a new app, and while setting up the database using South I get the following:
... line 11, in forwards
db.add_column('experiments_dailyreport', 'test_group_size',
orm['experiments.dailyreport:test_group_size'])
You cannot add a null=False column without a default value.
Given that this is a new table with no data in it, is there some way to force this migration?

You can force a migration using:
manage.py migrate --fake django-lean 0005
where 0005 is the version number of the migration. All that matters in your situation are:
having the correct database schema in the end
having South think that all migrations have been run
After that you can run the other migrations as normal. Alternatively, you can remove South, create the latest tables from django-lean using syncdb and then fake all the django-lean migrations.
Lastly, if you're certain that there's something wrong with the migration, it's worth contacting the django-lean developer(s) about this.