[Django]-How can I create a deep clone of a DB object in Django?

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27👍

✅

Googling "django deep copy" returns this on the first page: Copy Model Object in Django | Nerdy Dork

The code sample given is:

from copy import deepcopy
old_obj = deepcopy(obj)
old_obj.id = None
old_obj.save()

If I understand your question correctly, you will want to change some more fields before saving.

👤Marcin

1👍

I think this happens because survey assigned to survey_new on this line of code

survey_new = survey

An then when survey_new saved

survey_new.title = survey.title + ' -- Copy'
survey_new.owner = str(new_owner_id)
survey_new.created = datetime.now()
survey_new.pk = None
survey_new.save()

survey became equal to survey_new. For example you can check it so

id(survey)
# 50016784
id(survey_new)
# 50016784

or Django equivalent

survey.id
# 10
survey_new.id
# 10

To figure out the issue all required objects have to be collected before assignment

survey_section = survey.sections.all().order_by('order')
# ... all other questions and options 

survey_new = survey
survey_new.title = survey.title + ' -- Copy'
survey_new.owner = str(new_owner_id)
# ... your remaining code
👤Alexey Savanovich

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