On Wed, Nov 10, 2010 at 6:32 PM, Andrew Godwin <and...@aeracode.org> wrote:
> So, I've been trying to trace a bug that's been affecting me as well as > someone else I know, to do with ModelForms / the admin and CharFields > with null=True, blank=True, and unique=True > > The old ticket for this was closed as WONTFIX: > http://code.djangoproject.com/ticket/9590 > > However, I'd personally rather see the admin work with this (more common > than you think) combination of options; otherwise, there's no way to > make more than one model with one of these fields via the admin, and > it's basically useless. > > There is a way, it just requires some admin customization. See: http://stackoverflow.com/questions/454436/unique-fields-that-allow-nulls-in-django/1400046#1400046 > I'd propose we either ship a new CharField subclass (NullCharField, > perhaps), or add an option to the existing one, which when it gets > something in EMPTY_VALUES returns None, not u"". Then, modify ModelForm > (and thus the admin) to use this new subclass if the field has null=True > set. > > It's a pretty simple fix, and I don't think it's an excessively ugly > thing to add one more option/subclass, especially when the resulting > error is quite user-unfriendly ("This value must be unique" error beside > a non-required, blank textbox). > > I don't think we can do anything now that would suddenly, when people installed a new level of Django, start storing nulls in cases where previously empty strings had been stored. Wouldn't we then likely be creating a situation where a table column winds up with some "empty" values equal to empty strings an others nulls? Having just one "empty" value is the reason empty strings are forced for null values, according to the doc. Personally I may wish null had been chosen as the empty value but I'm not sure we can safely make that change at this point. (I am tired, though, so maybe I am missing something in how this would not be a backwards-incompatible change?) Karen -- You received this message because you are subscribed to the Google Groups "Django developers" group. To post to this group, send email to django-develop...@googlegroups.com. To unsubscribe from this group, send email to django-developers+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-developers?hl=en.
