#24171: (1054, "Unknown column '__col1' in 'field list'") when using values,
annotate and aggrregate
----------------------------------------------+-----------------------
Reporter: abdulhaq-e | Owner: nobody
Type: Bug | Status: new
Component: Database layer (models, ORM) | Version: 1.8alpha1
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Easy pickings: 0 | UI/UX: 0
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I will try my best here to explain when this comes up:
Say I have the following test model:
{{{
class Test(models.Model):
fieldA = models.ForeignKey(AnotherModel)
fieldB = models.IntegerField()
}}}
I want to sum the result of multiplying `fieldB` and `fieldC` where the
latter is obtained by spanning the relationship as such (for example):
`fieldA__ForeignKey2__ForeignKey3__fieldC`
To do this:
{{{
Test.objects.aggregate(Sum(F(`fieldA__ForeignKey2__ForeignKey3__fieldC`)*F('fieldB')))
}}}
The above will work fine:
But I want to use the new annotations features in v1.8 to make the
relationship spanning shorter:
{{{
Test.objects.annotate(fieldC=F(`fieldA__ForeignKey2__ForeignKey3__fieldC`)).aggregate(Sum(F('fieldC')*F('fieldB')))
}}}
This will also work fine. However, I want a `ValuesQuerySet` (i.e. I want
some specific fields). This will NOT WORK:
{{{
Test.objects.annotate(fieldC=F(`fieldA__ForeignKey2__ForeignKey3__fieldC`)).values('fieldC',
'fieldB').aggregate(Sum(F('fieldC')*F('fieldB')))
}}}
This will give the error in the title: `(1054, "Unknown column '__col1' in
'field list'")`. The error is definitely to do with fieldB and here is how
I proved it!:
This works:
{{{
Test.objects.annotate(fieldC=F(`fieldA__ForeignKey2__ForeignKey3__fieldC`)).values('fieldC',
'fieldB').aggregate(Sum(F('fieldC')))
}}}
And surprisingly, giving an alternate annotation to fieldB works! (of
course I can't use the field name as an alias name):
{{{
Test.objects.annotate(fieldC=F(`fieldA__ForeignKey2__ForeignKey3__fieldC`),
FIELDB=F('fieldB')).values('fieldC',
'FIELDB').aggregate(Sum(F('fieldC')*F('FIELDB')))
}}}
Is this normal behaviour!?
--
Ticket URL: <https://code.djangoproject.com/ticket/24171>
Django <https://code.djangoproject.com/>
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