relation "django_admin_log" already exists - django

when i try to run python manage.py migrate i run into following error
Upon running python manage.py run migrations it says no changes detected. and when i runserver it gives me warning that i have unapplied migrations as well.i have been searching internet for two hours but got not solution. Someone knowing the solution please share :)

The table in your database that stores migration data to keep track of what has been applied is out of date. Try running python manage.py migrate --fake

Try python manage.py makemigrations [app name] and if still, this does detect changes then delete the folder named migrations which is inside your application folder and then use this python manage.py makemigrations [app name]. Once migration happens successfully do the python manage.py migrate.

Don't Try This at Home
I faced this issue, i make two changes,
change AUTH_USER_MODEL, so i have one migraiton about it
second one add new field for my folder_model(migration name: folder_model 0021)
When my first migrate attempt(I already run makemigrations commands on local so i have migration files), it says;
django.db.migrations.exceptions.InconsistentMigrationHistory: Migration admin.0001_initial is applied before its dependency account.0001_initial on database 'default'
This error reiases because i change the AUTH_USER_MODEL in the middle of the project, normally you have to remove your database and fresh start from the beginnig(also truncate migrations etc.), according to Django doc -> https://code.djangoproject.com/ticket/25313
To fix this issue, you don't have to delete all migrations on db, just delete the migrations about admin(not from project just database)
After that just run
python manage.py migrate
It throws relation "django_admin_log" already exists. For this issue, run:
python manage.py migrate --fake
That's it, but not completely. Make fake migration act like you already make your all migrations successfully and save these on db. The issue came here that i have another migration about folder_model 0021 and with fake migration it doesn't applied to my database table but saved to db_migrations table.
So fix this issue, delete the folder_model 0021to database migration table (just 0021 not all folder_model migrations).
After delete just run python manage.py migrate
Everything is fine!

Related

Django migration delete and update

I have already had some migration files, and I made some changes in the model and did
python manage.py makemigrations
python manage.py migrate
After that in postgresql table django_migrations there is a row indicating I've applied that migration, let's call this migrationA.
I deleted the new generated migration file (migrationA), modified a small piece in my model and then did
python manage.py makemigrations
python manage.py migrate
This generate migrationB. I was hoping this can do the same as squashing migration files.
Will this kind of flow cause any trouble? I didn't see any trouble now but want to make sure this is a safe way to do things. In addition, is there any way to revert postgresql to the time before I applied migrationA?
Yes, it will cause trouble. All the migrations are stored in the migrations table and just deleting a migration will produce inconsistencies between your actual migrations and what's recorded.
Before deleting a migration and creating a new one, you need to first revert it by running ./manage.py migrate my_app number_previous_migration_name.

Django migrate fails when creating new table

We are fairly new to Django. We we have an app and a model. We'd like to add an 'Category' object to our model. We did that, and then ran 'python manage.py makemigrations'.
We then deploy our code to a server running the older code, and run 'python manage.py migrate'. This throws 2 pages of exceptions, finishing with 'django.db.utils.ProgrammingError: (1146, "Table 'reporting.contact_category' doesn't exist")'
This seems to be looking at our models.py. If we comment out Category from our model, and all references to it, the migration succeeds.
I thought that the point of migrations is to make the database match what the model expects, but this seems to require that the model match the database before the migration.
We clearly are doing something wrong, but what?
I believe you skipped some migration in the server, so now you are missing some tables (I have been in that situation. Ensure migrations directories are on your .gitignore. You CAN NOT check in migrations files, you have to run makemigrations on the server). This can be solved by tracing back up to the point the database and models files match, but it is a risky process if it is your production database, so you should make a full backup before proceeding, and try the process on a different computer before.
This would be my advice:
Delete migration files from the server.
Comment the models that rise the error.
Set the server's migration history to the point the
database is, using python manage.py makemigrations and python manage.py migrate --fake-initial (this will update the migration files without actually attempting to modify the database).
Uncomment the models that raise the error.
Run python manage.py makemigrations and python manage.py migrate.
If, after you comment the models that raise the exception, you get a different exception, you have to keep on commenting and attempting again. Once a migrations succeeds, you can uncomment all commented models and make an actual migration.
Remember to run python manage.py makemigrations if you made changes to the models.py then run python manage.py makemigrations
Both commands must be run on the same server with the same database

Django manage.py: Migration applied before its dependency

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

Deleted migration files- how to makemigrations without losing data

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/

django migration No migrations to apply

I have screwed up my database so I tried to redo it. I did:
1) deleted all tables via sql
2) deleted the migrations folder
So when I now do manage.py makemigrations myapp it is creating the migration folder and the initial.py file, which looks fine. Also the __init__.py is there. However, if i do manage.py makemigrations myapp I always get the message "No migrations to apply."
I looked up the database in the shell and the tables are not there.
I am using Django 1.8.
Django keeps track of all the applied migrations in django_migrations table.
So just delete all the rows in the django_migrations table that are related to you app like:
DELETE FROM django_migrations WHERE app='your-app-name';
and then do:
python manage.py makemigrations
python manage.py migrate
Django keeps track of all the applied migrations in django_migrations table.
So, you can follow this method:
Delete the related rows from django_migrations.
run python manage.py migrate.
I usually ran into that issue myself. Here is the workaround I found:
Replace your database sqlite3 with this
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': '<your_username>$<your_database_name>',
'USER': '<your_username>',
'PASSWORD': '<your_mysql_password>',
'HOST': '<your_mysql_hostname>',
}
}`
The fill in for can be found in the databases tab on your Pythonanywhere dashboard.
Push it to github from your Terminal and pull it down from Pythonanywhere Bash again. You may have to add this on Bash Console: pip install mysqlclient
As #Anush mentioned, Django does keep track of all of the migrations in the django_migrations table. As mentioned, you can use raw SQL to remove the migration row to reset Django's migration history for the concerned app.
DELETE FROM django_migrations WHERE app='my-app';
If you are uncomfortable deleting rows like this, then you can use Django's management command replacing my-app for the name of your app.
python manage.py migrate --fake my-app zero
That command will remove the migration history rows from the database leaving you to start your migration again from scratch. You will then need to:
Delete all of the migration files within your app's 'migrations' directory but ensure that the __init__.py file remains.
Ensure that your app's data models are set up as you need them
Make the migrations again with the command python manage.py makemigrations {your_app_name}. This will create the 0001_initial.py file within your app's migrations directory.
You will not be able to actually migrate the initial database migration because the database table already exists, so you will need to fake the migration with the command, python manage.py migrate my_app --fake-initial
Instead of run:
python manage.py migrate
just run:
python manage.py migrate --run-syncdb
If you have many problems and require a solution
Create a database backup (more than one if necessary)
My solution was to run the following query in the SQL shell
drop database database_name with (force);
This completely removes the database, be careful
It solved the error for me
Greetings
After running into this problem on Django 3.0 I spent an entire day troubleshooting this. Sharing this so that others would not need to. Most of the times running
python manage.py makemigrations
python manage.py migrate
Should solve the problem. I followed the above step after deleting the files in migrations folder (except init.py), however I was not able to solve the problem. I found that every time you run makemigrations, a python file called 000x_xxx.py is created in the migrations folder. I looked inside the file and found that all my required changes were there but it also had other create table operations that I did not need (i.e those tables had already been created). If you run migrate with --fake or --fake-initial, the whole execution will be faked (i.e executed without actually making any change in the database).
To solve the problem I opened the generated 0000x_xxx.py file and deleted the changes I wanted to make in the database and ran "python manage.py makemigrations" again. This created a new migration file with the changes I wanted. After that I ran the following command.
python manage.py migrate --fake-initial appname
This solved the problem. Not sure if this should be this complicated.