But I think the increment of the version column is the same with the example of Poll I mentioned in the previous post. If the transaction is not used, the read action is separated with the write action by default. The problem still can happen. Or do you have some special method to update this column? If so, please teach me. Many thanks!
On Mar 31, 1:34 pm, meppum <[EMAIL PROTECTED]> wrote: > I like the version column solution because it is more DB cross > compatible. Some databases don't support the same sort of timestamp as > others. But all DBs support integer columns. In terms of performance > it's probably the same or close to it as the comparison is done on the > database side. > > On Mar 31, 12:14 am, PENPEN <[EMAIL PROTECTED]> wrote: > > > I checked the transaction module of django. I think it could work. > > But why do you prefer this version column solution? Does it have > > better performance? > > > On 3月31日, 上午9时54分, meppum <[EMAIL PROTECTED]> wrote: > > > > I found this thread helpful. > > > >http://groups.google.com/group/django-users/browse_thread/thread/e9db... > > > > On Mar 30, 9:11 pm, Mark Green <[EMAIL PROTECTED]> wrote: > > > > > On Sun, 2008-03-30 at 17:49 -0700, meppum wrote: > > > > > The easiest way to deal with this is to create a "version" column that > > > > > gets updated with the current version number of the row in the > > > > > database. Increment this column value each time a save is performed on > > > > > that row. Override the save method on the model you want to perform > > > > > this check on (in your example the poll model), and check on commit > > > > > check that the value of the "version" colum in the database is LESS > > > > > THEN the value of the "verson" column you are about to commit. If it > > > > > is not, then throw an error. and rollback the transaction. > > > > > Ehm, and how would you "check on commit"? > > > > > -mark- Hide quoted text - > > > - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
