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Django: Converting an entire set of a Model's objects into a single dictionary

Posted by: admin November 30, 2017 Leave a comment


If you came here from Google looking for model to dict, skip my question, and just jump down to the first answer. My question will only confuse you.

Is there a good way in Django to entire set of a Model’s objects into a single dictionary? I mean, like this:

class DictModel(models.Model):
    key = models.CharField(20)
    value = models.CharField(200)


… with the result being a dictionary with the key/value pairs made up of records in the Model? Has anyone else seen this as being useful for them?


I just wanted to add is that my ultimate goal is to be able to do a simple variable lookup inside a Template. Something like:

{{ DictModel.exampleKey }}

With a result of DictModel.objects.get(key__exact=exampleKey).value

Overall, though, you guys have really surprised me with how helpful allof your responses are, and how different the ways to approach it can be. Thanks a lot.

Update October 2011:
This question is the top result if you Google “django model_to_dict”, which is actually pretty awful given that it solves a different problem than what I was asking.

What I wanted was to be able to map all of the instances in a queryset into a single dictionary with a specified model field as the key.
model_to_dict, on the other hand converts a single model instance into a dictionary.

Now, my needs at the time were pretty darn specific, and probably extremely rare (I can’t even remember the project I needed it for, or why). So I would be pretty surprised that anyone looking for information about model_to_dict is going to find my question actually useful. Sorry.

model_to_dict seems to be a much more common usage case than I had.

Update Dec 2011:
I changed the title to hopefully better reflect my original intent.


Does this need to create an actual dict? could you get by with only something that looked like a dict?

class DictModelAdaptor():
    def __init__(self, model):
        self.model = model

    def __getitem__(self, key):
        return self.model.objects.get(key=key)

    def __setitem__(self, key, item):
        pair = self.model()
        pair.key = key
        pair.value = item

    def __contains__(self, key):

You could then wrap a model in this way:

modelDict = DictModelAdaptor(DictModel)
modelDict["name"] = "Bob Jones"



You can also rely on django code already written ;).

from django.forms.models import model_to_dict
model_to_dict(instance, fields=[], exclude=[])


You are looking for the Values member of QuerySet which allows you to get a list of dictionaries from your query

Returns a ValuesQuerySet — a QuerySet
that evaluates to a list of
dictionaries instead of model-instance
objects. Each of those dictionaries represents
an object, with the keys corresponding
to the attribute names of model

>>> Blog.objects.values()
[{'id': 1, 'name': 'Beatles Blog', 'tagline': 'All the latest Beatles news.'}],
>>> Blog.objects.values('id', 'name')
[{'id': 1, 'name': 'Beatles Blog'}]


You want the in_bulk queryset method which, according to the docs:

Takes a list of primary-key values and
returns a dictionary mapping each
primary-key value to an instance of
the object with the given ID.

It takes a list of IDs, so you’ll need to get that first via the values_list method:

ids = MyModel.objects.values_list('id', flat=True)
model_dict = MyModel.objects.in_bulk(ids)


You can use the python serializer:

from django.core import serializers
data = serializers.serialize('python', DictModel.objects.all())


dict((x.name, getattr(o, x.name)) for x in o._meta.fields)



dict(((m.key, m.value) for m in DictModel.objects.all())

As suggested by Tom Leys, we do not need to get whole object, we can get only those values we need e.g.

dict(((m['key'], m['value']) for m in DictModel.objects.values('key', 'value')))

and if you need all values, it is better to keep whole object in dict e.g.

dict(((m.key, m) for m in DictModel.objects.all())


Perhaps I’m missing something, but Django objects have a __dict__ attribute which seems be what you want.


To get a map of all of the instances in a queryset into a single dictionary with a specified model field as the key, try doing this

from django.forms.models import model_to_dict
from myApp.models import myModel

allObjs = myModel.objects.all()
f = {}         # initialise the output
key = 'key'    # one of the fields from myModel

[f.update({x[key]: x}) for x in [model_to_dict(y) for y in allObjs]]
return f


To get values of a models into dictionary, add below code at the place where u need that dictionary

from models import DictModel

activity_map = dict(Plan.objects.values_list('key', 'value'))

activity_map is a dictionary which contains required information .

user = mymodel.objects.all()

You can also try

user.values_list() # getting as list


Or were you trying to do something like:

def someview(req):
    models = MyModel.objects.all()
    toTuple = lambda field: (getattr(field, 'someatt'), getattr(field, 'someotheratt'))  
    data = dict(map(toTuple,models))
    return render_to_response(template, data)