CODEWITHSUNDEEP
djangodjango-orm
Martin
Martin

Reputation: 4330

How to rename items in values() in Django?

I want to do pretty much the same like in this ticket at djangoproject.com, but with some additonal formatting. From this query

>>> MyModel.objects.values('cryptic_value_name')
[{'cryptic_value_name': 1}, {'cryptic_value_name': 2}]

I want to get something like that:

>>> MyModel.objects.values(renamed_value='cryptic_value_name')
[{'renamed_value': 1}, {'renamed_value': 2}]

Is there another, more builtin way or do I have to do this manually?

Upvotes: 183

Views: 105327

Answers (6)

burhanuddin abbas
burhanuddin abbas

Reputation: 198

Try passing as kwargs:

MyModel.objects.annotate(**{'A B C':F('profile_id')}).values('A B C')

In my case, there were spaces and other special characters included in the key of each value in the result set so this did the trick.

Upvotes: 0

Arpit Singh
Arpit Singh

Reputation: 3467

Without using any other manager method (tested on v3.0.4):

from django.db.models import F

MyModel.objects.values(renamed_value=F('cryptic_value_name'))

Excerpt from Django docs:

An F() object represents the value of a model field or annotated column. It makes it possible to refer to model field values and perform database operations using them without actually having to pull them out of the database into Python memory.

Upvotes: 164

Daniel Roseman
Daniel Roseman

Reputation: 599778

It's a bit hacky, but you could use the extra method:

MyModel.objects.extra(
  select={
    'renamed_value': 'cryptic_value_name'
  }
).values(
  'renamed_value'
)

This basically does SELECT cryptic_value_name AS renamed_value in the SQL.

Another option, if you always want the renamed version but the db has the cryptic name, is to name your field with the new name but use db_column to refer to the original name in the db.

Upvotes: 84

alejandrodnm
alejandrodnm

Reputation: 5640

From django>=1.8 you can use annotate and F object

from django.db.models import F

MyModel.objects.annotate(renamed_value=F('cryptic_value_name')).values('renamed_value')

Also extra() is going to be deprecated, from the django docs:

This is an old API that we aim to deprecate at some point in the future. Use it only if you cannot express your query using other queryset methods. If you do need to use it, please file a ticket using the QuerySet.extra keyword with your use case (please check the list of existing tickets first) so that we can enhance the QuerySet API to allow removing extra(). We are no longer improving or fixing bugs for this method.

Upvotes: 289

Sudip Bhattarai
Sudip Bhattarai

Reputation: 1154

I am working with django 1.11.6

( And the key:value pair is opposite to that of accepted answer )

This is how i am making it work for my project

def json(university):
    address = UniversityAddress.objects.filter(university=university)
    address = address.extra(select={'city__state__country__name': 'country', 'city__state__name': 'state', 'city__name': 'city'})
    address = address.values('country', 'state', "city", 'street', "postal_code").get()
    return address

Note that adding simultanous objects.filter().extra().values() is same as above.

Upvotes: 1

A.J.
A.J.

Reputation: 9015

Its more than simple if you want to rename few fields of the mode.

Try

projects = Project.objects.filter()
projects = [{'id': p.id, 'name': '%s (ID:%s)' % (p.department, p.id)} for p in projects]

Here i do not have a name field in the table, but i can get that after tweaking a little bit.

Upvotes: -6

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