.
Main point is that you:
- save your current database tables structure
- change your model tables
- scan for differences and create script
- then write changes to your database with automatically generated python script.
Sound's simple? I't not all so simple in fact. App that you need to learn is Django-south. Its main objectives are to provide a simple, stable and database-independent migration layer to prevent all the hassle schema changes over time bring to your Django applications. It has quite understandable tutorial here.
So if you're tired of ALTER'ing your tables and writing code to python Sqlite console or editing raw SQL, go get yourself a copy of south. It's an app that IMHO everybody should use/hear/understand.
It is meant to change old one and quite simple command 'manage.py syncdb' someday. For now go get yourself this tool and learn to use it. It took me about half an hour to understand basics.. So it's not hard (at first) :).
Brief look at usage:
1. Install app in some way. Use pip/easy_install script or simply put 'south' dir to your project root dir.
Add 'south', to your INSTALLED_APPS dictionary.
!IMPORTANT! you need to make syncdb after that. Another way wo will get an error with future commands.
2. Connect existing app's to migrations. Use command python manage.py convert_to_south myapp to convert your app from syncdb ready to south migratable. Or you can run python manage.py schemamigration newappname --initial to add south migrations ability to your new app. In general it will create directory 'migrations' inside your app directory.
3. Change your model. I dont think you need separate stop here. But... Just in case add some field to your django model like bollean or text and/or edit your existing field rather by adding 'null=True' for e.g.
4. Create your migration. It can be done by command python manage.py schemamigration newappname --auto to create your migration script. you can check it in your app's 'migrations' dir. It has numbers in the beginning with migration number.
5. Run your migration. It is done by command python manage.py migrate appname or even without an app name: python manage.py migrate to migrate all apps. Thats it.
Hope you'll never use 'syncdb' again for complex tasks like this. I'm adding it to my base developer tools. And you?
Main point is that you:
- save your current database tables structure
- change your model tables
- scan for differences and create script
- then write changes to your database with automatically generated python script.
Sound's simple? I't not all so simple in fact. App that you need to learn is Django-south. Its main objectives are to provide a simple, stable and database-independent migration layer to prevent all the hassle schema changes over time bring to your Django applications. It has quite understandable tutorial here.
So if you're tired of ALTER'ing your tables and writing code to python Sqlite console or editing raw SQL, go get yourself a copy of south. It's an app that IMHO everybody should use/hear/understand.
It is meant to change old one and quite simple command 'manage.py syncdb' someday. For now go get yourself this tool and learn to use it. It took me about half an hour to understand basics.. So it's not hard (at first) :).
Brief look at usage:
1. Install app in some way. Use pip/easy_install script or simply put 'south' dir to your project root dir.
Add 'south', to your INSTALLED_APPS dictionary.
!IMPORTANT! you need to make syncdb after that. Another way wo will get an error with future commands.
2. Connect existing app's to migrations. Use command python manage.py convert_to_south myapp to convert your app from syncdb ready to south migratable. Or you can run python manage.py schemamigration newappname --initial to add south migrations ability to your new app. In general it will create directory 'migrations' inside your app directory.
3. Change your model. I dont think you need separate stop here. But... Just in case add some field to your django model like bollean or text and/or edit your existing field rather by adding 'null=True' for e.g.
4. Create your migration. It can be done by command python manage.py schemamigration newappname --auto to create your migration script. you can check it in your app's 'migrations' dir. It has numbers in the beginning with migration number.
5. Run your migration. It is done by command python manage.py migrate appname or even without an app name: python manage.py migrate to migrate all apps. Thats it.
Hope you'll never use 'syncdb' again for complex tasks like this. I'm adding it to my base developer tools. And you?
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