On 9/12/06, Gary Doades <[EMAIL PROTECTED]> wrote: > As an example, I have a table (product) that is referenced by 11 other tables > (booking, history, rates, invoice, payroll, timesheets etc.). Those tables > contain upwards of 10 million rows in the existing application. I certainly > don't want those records to be deleted just because (by whatever means) > someone tried to delete a product!!
There are some checks in place for this; the admin app, for example, will display a confirmation page before allowing a delete, and that page lists every related object that will be deleted. Much of the problem with this is that certain databases *cough*sqlite*cough*mysql*cough* have issues with specifying delete behavior at the SQL level. I've written this up at some length on the Django developers list[1], but here's the executive summary: * Postgres is the only DB which supports the full range of "ON DELETE" and "ON UPDATE" options consistently. * MySQL supports them *only* when every table involved is InnoDB. * SQLite uses "ON CONFLICT", and whether it actually behaves properly is highly debatable; per its own documentation, it does not enforce foreign key constraints. If you read through the referenced thread, there's discussion of some options but it's a tough problem that we don't yet have a good solution for. [1] http://groups.google.com/group/django-developers/browse_thread/thread/bae9fcc645c4b04c/#hdropened4c65ac76d85c5c34 -- "May the forces of evil become confused on the way to your house." -- George Carlin --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users -~----------~----~----~----~------~----~------~--~---
