Brant Harris wrote:
> I now have a working solution to ticket #12.
> I've added some code to management.py that allows one to run:
>>django-admin.py transition <app>
>>django-admin.py sqlupdate <app>
> Now, sqlupdate looks at the "app.transition.py
" file, and executes the
> changes accordingly, spitting out:
> DROP TABLE `app_departments_users`;
> DROP TABLE `app_medias`;
> ALTER TABLE `app_documents` ADD COLUMN `rating` integer NOT NULL;
Erm. Can you create a NOT NULL Column without a default in an ALTER
Statement? I know you can't in MSSQL.
> CREATE TABLE app_documents_attachments (
> id mediumint(9) unsigned auto_increment NOT NULL PRIMARY KEY,
> document_id integer NOT NULL REFERENCES app_documents (id),
> file_id integer NOT NULL REFERENCES app_files (id),
> UNIQUE (document_id, file_id)
> I have only tested this with mysql, but it seems to be working well.
> I'm still adding comments to the code, should I add a patch to #12 or
> should I send it to someone?
It's still missing something.
Well, two things, really. Plus the bit mentioned above, which is a
technicality, though it's an important consideration.
Let's take a use case:
You create a FooApp for django. You fiddle with the tables, and eventually
release FooApp 1.0.
You find that for the next version you want two more tables: Bar and Baz, so
you add a transition file to create Bar and Baz, and release FooApp 2.0
For the next version (3.0) you want a table Quux, and you find that rather
than having a "price" field in Bar you actully want it to be in "net", "tax"
and "commission", and not use the "price" field at all.
Question number 1: How does your transition file cope with someone who *was*
using FooApp 1.0 upgrading directly to 3.0?
Question number 2: Assuming I can, as standard *calculate* the columns
"net", "tax" and "commission" for the alreayd existing "price" column, how
do I go about doing so at database upgrade time.
My own particular take on this is up at
but I haven't had the time to actually code up a patch, and I'm not certain
it's the correct solution anyway. I'd appreciate thoughts, though.
Giles Antonio Radford, alias Moof
"Too old to be a chicken and too young to be a dirty old man"
Serving up my ego over at <http://metamoof.net/