So I've created a new model in Django, then executed both python manage.py makemigrations and python manage.py migrate in the right order. But then for some reason I accidentally dropped the table(relation) in PgAdmin (I know it sounds silly). So I tried deleting all the files in migrations folder but the init.py file. Then I ran the two commands above again, but could see no table in the PgAdmin. What should I do, aside from creating a table myself in PgAdmin?
Thanks in advance.
It won't work, because entry for all the migrations are already stored inside a table named django_migrations. So even if you run makemigrations after deleting all the migration files, it won't create a new one. So here is three ways you can fix it.
One: Drop DB(if data is not important)
Drop database and create a new one. Run makemigrations and migrate command.
Two: Create that table manually
If you already deleted all the migration files, you better restore them. You can use git for this: git checkout /path/to/migration/folder. Then you can manually create the table.
Three: Delete entries from django_migrations
I assumed you have deleted all the migration files. So this part covers the whole project. But #DenizKaplan has explained better way to do this.
If you are not using git, or no way to restore these files, then you can follow these steps:
Backup your database
Delete all entries from djang_migrations table
Run ./manage.py makemigrations to generate migration file
Run ./manage.py migrate <your lost app> to migrate your app(which you have lost in DB).
Run ./manage.py migrate --fake to fake the rest of apps.
There are some steps you need to check. If you have an empty output after makemigrations operations, you may need to check for django_migrations table to remove rows related to apps that you have working with. If this won't help at first place, you need check INSTALLED_APPS, maybe you may accidently delete apps. If all these not work, please give some detailed information about the error.
I created a migration file using python3 manage.py makemigrations my_app. However I ran that command by mistake. Is it safe just to delete the newly created non-processed migration file? Or is there something else that needs to be done?
Until you run migrate there's no record of the migration other than the existence of the file in the migrations directory. So yes, it's perfectly safe to delete it.
If you have not run migrations, its cool. Only take care that it does not create any dependency issues. For example if running makemigrations created 5 migration files in 5 different folders, Be sure to delete each one of them.
But if the migration was run and somehow could not be completed, then you should revert back the changes also before deleting the migration files.
Be careful with it and see django_migrations table to be extra sure.
When running python manage.py migrate I encounter this error:
django.db.migrations.exceptions.InconsistentMigrationHistory: Migration
<appname>.0016_auto_<date2>_<time2> is applied before its dependency
<appname>.0001_squashed_0015_auto_<date1>_<time1>
running showmigrations returns:
<appname>
[X] 0001_squashed_0015_auto_<date1>_<time1> (15 squashed migrations)
[X] 0016_auto_<date2>_<time2>
[ ] 0017_<modelname>_squashed_0019_auto_<date3>_<time3> (3 squashed migrations)
I was trying out django-extensions yesterday, when it all got messed up after me running some direct SQL queries and I reset hard using git. I'm still learning about migrations, so I don't understand what is wrong, since it seems to me that both migrations already have been applied.
Thank you for your help!
This worked for me. I thank my coworker for sharing this knowledge after I searched online for many hours.
Start your db shell
python manage.py dbshell
Use the database you want. If you don't know, run .databases (SQLite) or SHOW databases
mysql>use <database_name>;
Retrieve all the migrations under your app
mysql> select * from django_migrations where app='<app>';
You will see the output with ids next to all migrations. Look at the migration you want to drop. Say the id is 361
mysql> delete from django_migrations where id=361;
You have squashed the migrations, so one of the dependencies that 0016_auto_<date2>_<time2> had is now part of the newly created squashed migrations. Meanwhile the 0016_auto_<date2>_<time2> has already been run and now you're trying to run the squashed migration.
I personally don't know if there's any way to fix this automatically. You will need to fix the issues yourself. If you have version control, revert these changes and try to rethink how you should squash the migration without affecting old ones.
I have solved this problem when i did (custom user model) by this steps:
delete this file :
migrations\0001_initial.py
delete this :
db.sqlite3
put this code in settings.py :
AUTH_USER_MODEL = 'users.CustomUser'
Then do (makemigrations) then (migrate )
run server .. the problem solved :)
i have used this link it is help me to solve the problem of dependency :
https://docs.djangoproject.com/en/3.1/topics/auth/customizing/
Due to limitations of Django’s dynamic dependency feature for swappable models, the model referenced by AUTH_USER_MODEL must be created in the first migration of its app (usually called 0001_initial); otherwise, you’ll have dependency issues.
In addition, you may run into a CircularDependencyError when running your migrations as Django won’t be able to automatically break the dependency loop due to the dynamic dependency. If you see this error, you should break the loop by moving the models depended on by your user model into a second migration. (You can try making two normal models that have a ForeignKey to each other and seeing how makemigrations resolves that circular dependency if you want to see how it’s usually done.)
run this python manage.py dbshell
INSERT INTO public.django_migrations(app, name, applied)
VALUES ('YOUR_APP_NAME, '0017_<modelname>_squashed_0019_auto_<date3>_<time3>', now());
and you should be fine. If Your migration was changing a lot to the database, then I am afraid it won't be that easy to fix it.
you need to fake migrations and migrate again
just make sure that you have a backup from your data because when you migrate again you need to delete apps table.
make sure that you look at show migrations and migrate un migrated apps by its sequence
Edit the dependencies of the conflicting migration, so that it no longer references the already applied migration.
Then run python manage.py migrate again and it should be fixed.
Warning: this only work suppossing that the state of the database matchs the state you get having applied the conflicting migration.
I had the same issue on 2020 with Django 3.0.6.
I tried all the relevant answers with no success. So I went in my database and deleted all the tables. You must export the relevant tables if you have done lot of work. I mainly delete django files in my database. And after, run:
python manage.py makemigrations <my-app>
And:
python manage.py migrate
Export your relevant tables if any.
First back up your database before resolving the conflicts, (Use "python manage.py dumpdata > db.json" for SQLite).
Execute python manage.py dbshell, to access the database.
Delete the migrations rows that are having conflicts from the django_migrations table.
Rename the tables conflicting in the database
Execute the makemigrations and migrate commands
After successful migrations, Drop the newly readded tables and finally restore the previously renamed tables to match the migrations need
I had the same problem, and here's how I solved it.
The following is my error message
File "/usr/local/lib/python3.11/site-packages/django/db/migrations/loader.py", line 327, in check_consistent_history
raise InconsistentMigrationHistory(
django.db.migrations.exceptions.InconsistentMigrationHistory: Migration aaaa.0024_campaign_template is applied before its dependency bbbb.0005_templatemodel_from_template on database 'default'.
My solution
python manage.py migrate bbbb
python manage.py migrate
Because I changed the Django's app name in batches, the application order was not consistent when applied to the database. The bbbb that aaaa relies on was not created first, so I manually created the bbbb first
Migration file is not created for all app:
step 1:
create migration folder and add __init__.py file for all app
step 2:
delete db.sqlite3 database
step 3:
python manage.py migrate
python manage.py makemigrations
Delete all of your migrations folder
Delete the database(sqlite3)
Then run the makemigrations and migrate command
Delete the migration files.
Run:
python manage.py migrate
python manage.py makemigrations
python manage.py migrate
python manage.pyrunserver
I changed a field on a model class (which has no classes point to it, only one foreign key pointing out of it). Somehow, this stuffed up my migrations and it keeps saying "django.db.migrations.graph.NodeNotFoundError:" looking for migration files that do not exist.
I accidentally deleted several files in my 'migrations' folder.
My database contains a lot of data, and I do not want to break it.
Will I lose any data if I:
Remove the table that caused the problem in the first place (psql, \d, DROP TABLE tablename)
delete all my migration files
Re run the migration from the start?
./manage.py makemigrations
./manage.py migrate
Can anyone recommend another way of fixing this?
Here is the traceback:
http://dpaste.com/0Y1YDXS
Aren't you using git so that you can get your migration files back? If not, install and use it, starting now
I would suggest:
make a backup/dump of your database first, in case something goes wrong
Delete all migrations
Empty migration table in psql
call makemigrations
call migrate --fake-initial
Empty the django_migrations table:
delete from django_migrations;
Remove all the files in migrations folders in each and every app of your project.
Reset the migrations for the "built-in" apps:
python manage.py migrate --fake
Create initial migrations for each and every app:
python manage.py makemigrations your_app_name
Final step is to create fake initial migrations:
python manage.py migrate --fake-initial
See here https://micropyramid.com/blog/how-to-create-initial-django-migrations-for-existing-schema/
I am trying to migrate a database, after modifying the schema in the models.py file of my app in Django. When I try to migrate using ./manage.py migrate <app-name>, it gives the following message:
! These migrations are in the database but not on disk:
As I went through the schemamigration_table and the files, I noticed that for my last schema migration, the file (which added a table and a column in another table successfully) is not present for some reason. Is there any way I could perform my migration without resetting the database?
Yes,
If you are absolutely confident about the migration to have already applied to the database, You can safely use the --fake option.
./manage.py migrate <app-name> --fake
This would forward the migrations to the most recent migration.
--fake: Records the migration sequence as having been applied, but doesn’t actually run it. Useful for Converting An App.