Suppose, we have a db's backup and a django program. The program do not have any migrations. First we restore db, that has created table and data. Now we want to make migrations from available db. Is it possible or not?
Yes, Django has the inspectdb method, which is described here.
But if the Django app already has the models defined that correspond to the backed up database, then you can just run makemigrations (follow #Shafikur's instructions).
Just go to your corresponding database terminals and delete all the records from you django_migrations table with
delete from django_migrations;
Go to terminal and run remove all files in migrations folder with
rm -rf <app>/migrations/
Reset all the migrations of the Django's built-in apps like admin with the command
python manage.py migrate --fake
Create initial migrations for each and every app:
python manage.py makemigrations <app>
To create initial fake migrations just run
python manage.py migrate --fake-initial
Related
i am new to django developement after making changes to my model i tried to run the command python manage.py makemigrations my_app
it detects changes in my model and shows me the message
todoapp/migrations/0001_initial.py
- Create model confess
- Create model UserChoice
- Create model comment
but on executing python manage.py migrate my_appcommand i've got this message
No migrations to apply.
i usually do this after making changes in models, i don't know what happened now.
plss help me.
Firstly, try
python manage.py makemigrations my_app
python manage.py migrate
If this does not work and the project is still in development:
Delete migrations folder and pycache folder.
Delete db.sqlite3 (your database).
Make and apply migrations again.
I think this will work.
Delete all migrations files and __pychache__except__init__.py from your project and app. Also db.sqlite3 database then rerun makemigrations and migrate commands. It should solve your issue.
In my django app path, the migrations folder was deleted, but I want to recover it, when executing migrate command:
python manage.py migrate --fake api.desktops
CommandError: App 'api.desktops' does not have migrations (you cannot selectively sync unmigrated apps)
How can reset those app?
If your database and and app are synchronised you should be able to do the following:
./manage makemigrations <app_name>
./manage migrate <app_name> --fake
If the database is out of sync you can also perform the same as above but will need to manually alter your database to align with the new migration structure.
There are three migration commands in Django:
python manage.py makemigrations
python manage.py migrate
python manage.py syncdb
In what order do these commands should be executed in terms of workflow of a basic project?
I am using Version: 1.8
syncdb is deprecated and does the same as migrate.
Whenever you make a change to your models, and when you first create them, each time you'd want to first run makemigrations to create the migration files, then migrate to apply them to your database.
I have a production web project running with a decent amount of data in the MySQL db. I am trying to update the database with some changes to an app called "enterlink." I've made new elements in the existing models and created new models altogether. Before this migration, I have never touched the schema of the db since originally running syncdb to create it. When I run: "python manage.py makemigrations enterlink" the below output appears(pic). My question is, why is this happening? The DB already includes all the models that it lists in the picture so why is it registering those lists of models? When I go to finish the migration by doing "python manage.py migrate" or "python manage.py migrate --fake enterlink" (pic again), I get an output shown but my database schema remains identical to the old db and any new code generates errors. Can anyone tell me what is likely the problem? I would be really appreciative of any advice. It's been very frustrating since I'm not sure what I'm missing.
What you have done is that you have ran the command python manage.py syncdb before running python manage.py makemigrations myapp and python manage.py migrate myapp. That is why syncdb created the database schema and the migration was faked because schema already exists. I will suggest to use python manage.py makemigrations myapp and python manage.py migrate myapp and not to use syncdb as its deprecated in Django 1.7.
If you change anything in your model, just run makemigrations and migrate command. Syncdb isn't necessary.
This question and relevant answers are intriguing me. Thus I want to share my experience on maintaining live database and migrations.
Tested in django1.5.5
Initializing the database:
./manage.py syncdb --noinput
./manage.py migrate
./manage.py syncdb
Now I have created the database.
Doing a migration for an app:
./manage.py schemamigration myapp --initial
./manage.py migrate myapp --fake
Now do necessary changes in your model
./manage.py schemamigration myapp --auto
./manage.py migrate myapp
Im newbie for schemamigration too, but i will explain how it works for me:
First you create app and then
./manage.py sycndb, so tables are created then you can
./manage.py makemigrations myapp --initial
so now initial migrations are created and you should apply them
./manage.py migrate myapp
now you can change your models : add,change fields, anything you want and then
./manage.py makemigrations myapp --auto
this will create migrations for changes and now you need to apply them
enter code here./manage.py migrate myapp
so this actually will create new tables in db
I'm deploying a project on a new development environment.
As I'm using South I did:
$ python manage.py syncdb --all
$ python manage.py migrate --fake
I used syncdb --all to apply actual state of models.
Then migrate --fake to mark all models as migrated.
But after that, my model is not on the last version (missing fields)
What am I doing wrong ?
I assume all my modifications have migrations.
If I do
$ python manage.py syncdb
It seems to create the first state since when I used South (that is expected)
But then
$ python manage.py migrate
Some tables appears as already created
Actually this, should have been fine for my case
$ python manage.py syncdb --all
$ python manage.py migrate --fake
Having to redeploy my app recently, I faced the same issue.
I just realized that I had a double initial migration on the model that were causing the problem
0001_initial.py
0002_initial.py
0003_auto__add_field_mytable_myfield.py
I simply deleted & renamed
0001_initial.py
0002_auto__add_field_mytable_myfield.py
Then redone the whole database deployment (obviously not forgetting to update the already applied migrations on my other hosts)
--fake option does not avoid errors while trying to create new migrations. It records that migrations have applied without actually applying them.
Also, you need --ignore-ghost-migrations or --delete-ghost-migrations to achieve what you are looking for.
To convert an existing project to south, you first need to convert the app
Now, if you have already run --fake, to recover, you can do this:
Go to ./manage.py dbshell
DELETE FROM south_migrationhistory WHERE id > 0; //Note that this would delete everything in the table.
If you want to remove migrations of a specific app,
DELETE FROM south_migrationhistory WHERE app_name = 'blah'