[Django] #21838: What about adding a .reload() method to the QuerySet API?
Django
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Reporter: fero@… | Owner: nobody
Type: New feature | Status: new
Component: Database layer (models, ORM) | Version: 1.6
Severity: Normal | Keywords: queryset
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 1 | UI/UX: 0
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Sometimes it is needed to reload data from database backend. It could be
necessary in example to benefit of some values type-casting applied by the
database backend module.
In various Django projects I developed I find useful a simple method
QuerySet.reload() like this:
{{{
def reload(self):
"""Reload QuerySet from backend."""
pks_list = self.values_list('pk')
return self.model.objects.filter(pk__in=pks_list)
}}}
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Ticket URL: <https://code.djangoproject.com/ticket/21838>
Django <https://code.djangoproject.com/>
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Django
Reporter: fero@… | Owner: nobody
Type: New feature | Status: closed
Component: Database layer | Version: 1.6
(models, ORM) | Resolution: wontfix
Severity: Normal | Triage Stage:
Keywords: queryset | Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 1 | UI/UX: 0
Changes (by aaugustin):
* status: new => closed
* needs_better_patch: => 0
* resolution: => wontfix
* needs_tests: => 0
* needs_docs: => 0
Comment:
This will be very inefficient for large querysets. I'm -1 on this
implementation.
As far as I know, the easiest way to reload a QuerySet is simply
`qs.filter()`.
It will clone the queryset and wipe the result cache.
You may get different rows if the database has changed since the QuerySet
was first evaluated. That's the behavior I would expect.
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Ticket URL: <https://code.djangoproject.com/ticket/21838#comment:1>
Django
Reporter: fero@… | Owner: nobody
Type: New feature | Status: closed
Component: Database layer | Version: 1.6
(models, ORM) | Resolution: wontfix
Severity: Normal | Triage Stage:
Keywords: queryset | Unreviewed
Has patch: 0 | Needs documentation: 0
Easy pickings: 1 | UI/UX: 0
Comment (by fero@…):
Thanks I checked it out, I didn't know about this feature.
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Ticket URL: <https://code.djangoproject.com/ticket/21838#comment:2>
Django
Reporter: fero@… | Owner: nobody
Type: New feature | Status: closed
Component: Database layer | Version: 1.6
(models, ORM) |
Keywords: queryset | Triage Stage:
| Unreviewed
Easy pickings: 1 | UI/UX: 0
Comment (by Rich Rauenzahn):
FYI: This is a duplicate of https://code.djangoproject.com/ticket/22553
filed a year later that suggests using .all(), and fixes the docs to point
that feature out.
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Ticket URL: <https://code.djangoproject.com/ticket/21838#comment:3>