Django Postgresql ArrayField aggregation

Question

In my Django application, using Postgresql, I have a model with an ArrayField of CharFields. I would like to know if there\'s a DB way to aggregate and get a list of all the

Answer 1

In PostgreSQL you can do the following:

SELECT DISTINCT UNNEST(array_column) FROM the_table;

So if your model looks something like

class TheModel(models.Model):
    # ...
    array_field = ArrayField(models.CharField(max_length=255, blank=True),\
                             default=list)
    # ...

the Django equivalent is:

from django.db.models import Func, F
TheModel.objects.annotate(arr_els=Func(F('array_field'), function='unnest'))\
                .values_list('arr_els', flat=True).distinct()