[Django]-Flush just an app not the whole project

You can do this with the migrate command which takes two positional arguments:

Updates database schema. Manages both apps with migrations and those without.

positional arguments:

app_label
App label of an application to synchronize the state.
migration_name
Database state will be brought to the state after that
migration. Use the name “zero” to unapply all migrations.

So running a migrate zero followed by a migrate will clear only the data for the given app.

$ python manage.py migrate ${APPNAME} zero
$ python manage.py migrate ${APPNAME}    

For later versions of Django try in the Django shell:

from django.apps import apps
my_app = apps.get_app_config('my_app_name')
my_models = my_app.get_models()
for model in my_models:
    model.objects.all().delete()

More on the apps module can be found here.
Of course, you could convert this to a management command yourself using the management infrastructure.

I also needed something to empty only certain apps. I came up with this solution. This worked for mysql. It could be that the code needs to be changed for other databases.

The main idea is not to do the whole ‘flush’. Instead I get only what I want, with a grep from ‘sqlflush’. You can also put everything in one line. For readability I split it up.

BEGIN="BEGIN; SET FOREIGN_KEY_CHECKS = 0;"
TRUNCATE=`./manage.py sqlflush |egrep " \\\`app1_| \\\`app2_"`
END="SET FOREIGN_KEY_CHECKS = 1; COMMIT;"

echo $BEGIN $TRUNCATE $END | ./manage.py dbshell