That's an interesting perspective actually.. "Don't be a slave of your mind (or ORM)"
Cal On Wed, Jan 2, 2013 at 12:01 PM, Larry Martell <larry.mart...@gmail.com>wrote: > On Wed, Jan 2, 2013 at 4:29 AM, George Lund <gl...@mintel.com> wrote: > > I'm trying to bulk-delete several million rows from my database. > > > > The docs for Django 1.3 say "this will, whenever possible, be executed > > purely in SQL". A pure-SQL delete is what I want in this case, so that's > > fine. > > > > However, the code is never getting as far as running any SQL. > > > > Interrupting the script shows that the delete method on the QuerySet is > > trying to use a "Collector" to construct model instances for each row I'm > > trying to delete. This is going to take too long (and may in fact consume > > all the memory available) -- I don't think it's practical to wait in this > > case. (I've tried waiting over half an hour!) > > > > (I'm looking at django.db.models.query.QuerySet.delete and > > django.db.models.deletion.Collector.collect / Collector.add.) > > > > What's the point in doing the delete "purely in SQL" if all of the > objects > > are getting constructed anyway? Why do they need to be "collected" before > > the SQL DELETE is run? The model instance in this case has no child > rows, to > > which the delete might need to be cascaded. > > > > Meanwhile I can construct the SQL by hand easily enough, but I feel this > > isn't doing things the right way. > > I've had this discussion with other developers. Many feel they need to > slavishly adhere to the ORM and if you don't you're some type of evil > entity. I could not disagree more. Django and the ORM are tools, and > should be used only when they are the right tools for the job. I'd > just go ahead and do the delete in SQL. > > -- > You received this message because you are subscribed to the Google Groups > "Django users" group. > To post to this group, send email to django-users@googlegroups.com. > To unsubscribe from this group, send email to > django-users+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/django-users?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
