[Django] #29567: It raise FieldError when the F() function uses a forign key field.

[Django]

#29567: It raise FieldError when the F() function uses a forign key field.
-----------------------------------------+------------------------
Reporter: HongWeipeng | Owner: nobody
Type: Bug | Status: new
Component: Uncategorized | Version: 2.0
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-----------------------------------------+------------------------
```
class B(models.Model):
name = models.CharField(max_length=10)

class A(models.Model):
name = models.CharField(max_length=10)
b = models.ForeignKey('B', on_delete=models.CASCADE)
```
And then:
```
A.objects.all().update(name=F('b__name'))

raise FieldError("Joined field references are not permitted in this
query")
django.core.exceptions.FieldError: Joined field references are not
permitted in this query
```

--
Ticket URL: <https://code.djangoproject.com/ticket/29567>
Django <https://code.djangoproject.com/>
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[Django]

#29567: It raise FieldError when the F() function uses a forign key field.

-------------------------------+--------------------------------------

Reporter: HongWeipeng | Owner: nobody
Type: Bug | Status: new
Component: Uncategorized | Version: 2.0

Severity: Normal | Resolution:

Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0

-------------------------------+--------------------------------------
Description changed by HongWeipeng:

Old description:

> ```
> class B(models.Model):
> name = models.CharField(max_length=10)
>
> class A(models.Model):
> name = models.CharField(max_length=10)
> b = models.ForeignKey('B', on_delete=models.CASCADE)
> ```
> And then:
> ```
> A.objects.all().update(name=F('b__name'))
>
> raise FieldError("Joined field references are not permitted in this
> query")
> django.core.exceptions.FieldError: Joined field references are not
> permitted in this query
> ```

New description:

{{{#!python

class B(models.Model):
name = models.CharField(max_length=10)

class A(models.Model):
name = models.CharField(max_length=10)
b = models.ForeignKey('B', on_delete=models.CASCADE)
}}}
And then:

{{{#!python
A.objects.all().update(name=F('b__name'))

raise FieldError("Joined field references are not permitted in this
query")
django.core.exceptions.FieldError: Joined field references are not
permitted in this query
}}}

--

--
Ticket URL: <https://code.djangoproject.com/ticket/29567#comment:1>

[Django]

#29567: It raise FieldError when the F() function uses a forign key field.

-------------------------------+--------------------------------------
Reporter: HongWeipeng | Owner: nobody
Type: Bug | Status: closed
Component: Uncategorized | Version: 2.0
Severity: Normal | Resolution: duplicate

Keywords: | Triage Stage: Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0

-------------------------------+--------------------------------------
Changes (by Dan Collins):

* status: new => closed
* resolution: => duplicate

Comment:

Duplicate of (wontfix) #14104, see also
https://docs.djangoproject.com/en/dev/topics/db/queries/#updating-
multiple-objects-at-once

--
Ticket URL: <https://code.djangoproject.com/ticket/29567#comment:2>