What is the easiest way to clear a database from the CLI with manage.py in Django?

Question

I am using Django to build a website with MySQL. Now as I am learning so I need to change the Model very often so I want that all tables get cleared and new table get created.

But syncdb doesn't touch existing tables. Is there any better way to handle this problem?

Chemotropism

Answer 1

If you don't care about data:

Best way would be to drop the database and run syncdb again. Or you can run:

For Django >= 1.5

python manage.py flush

For Django < 1.5

python manage.py reset appname

(you can add --no-input to the end of the command for it to skip the interactive prompt.)

If you do care about data:

From the docs:

syncdb will only create tables for models which have not yet been installed. It will never issue ALTER TABLE statements to match changes made to a model class after installation. Changes to model classes and database schemas often involve some form of ambiguity and, in those cases, Django would have to guess at the correct changes to make. There is a risk that critical data would be lost in the process.

If you have made changes to a model and wish to alter the database tables to match, use the sql command to display the new SQL structure and compare that to your existing table schema to work out the changes.

https://docs.djangoproject.com/en/dev/ref/django-admin/

Reference: FAQ - https://docs.djangoproject.com/en/dev/faq/models/#if-i-make-changes-to-a-model-how-do-i-update-the-database

People also recommend South ( http://south.aeracode.org/docs/about.html#key-features ), but I haven't tried it.

Oarlock

South is really, really good for automatically handling migrations. Takes a bit of getting used to, but it saves a lot of hassle dropping and recreating databases during development, and is a must-have once your site is live and you need to alter the db structure while you have precious data in it. – Sontag

RESET COMMAND DEPRECIATED. In Django 1.5 the command has been updated to flush. try using python manage.py flush or python manage.py flush --noinput to skip the interactive prompt. – Supplementary

South has been deprecated. Refer here. And the link you've given here is broken. – Tymbal

It looks like the command is now django-admin flush according to the docs – Titos

Answer 2

Using Django Extensions, running:

./manage.py reset_db

Will clear the database tables, then running:

./manage.py syncdb

Will recreate them (south may ask you to migrate things).

Fleurette

@becko execute this first : pip install django-extensions – Hipolitohipp

Answer 3

I think Django docs explicitly mention that if the intent is to start from an empty DB again (which seems to be OP's intent), then just drop and re-create the database and re-run migrate (instead of using flush):

If you would rather start from an empty database and re-run all migrations, you should drop and recreate the database and then run migrate instead.

So for OP's case, we just need to:

1. Drop the database from MySQL
2. Recreate the database
3. Run python manage.py migrate

Amerind

It would be useful to add commands for steps 1 and 2. – Hilaria

@Hilaria those commands need to be run directly on database - so, outside the scope of Django. If you are asking how to drop/create the database on MySQL, those are usual SQL: DROP DATABASE <name> and CREATE DATABASE <name> – Amerind

Answer 4

Quickest (drops and creates all tables including data):

./manage.py reset appname | ./manage.py dbshell

Caution:

• Might not work on Windows correctly.
• Might keep some old tables in the db

Thallic

reset already runs the SQL, so no need to pipe to dbshell. If you use the sqlreset command, then that would just print out the SQL, which you could pipe to the shell for execution, but it's an unnecessary step. – Haulm

Answer 5

You can use the Django-Truncate library to delete all data of a table without destroying the table structure.

Example:

1. First, install django-turncate using your terminal/command line:

pip install django-truncate

2. Add "django_truncate" to your INSTALLED_APPS in the settings.py file:

INSTALLED_APPS = [
    ...
    'django_truncate',
]

3. Use this command in your terminal to delete all data of the table from the app.

python manage.py truncate --apps app_name --models table_name

Easton