What is the best way to store an array of integers in a django database?
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6 Answers
I'm using ArrayField: https://docs.djangoproject.com/en/2.1/ref/contrib/postgres/fields/#querying-arrayfield
eg.
class Place(models.Model):
nearby_places_ids = ArrayField(models.IntegerField(null=True, blank=True), null=True, blank=True)
with usage:
place.nearby_places_ids = [1,2,3]
place.save()
models.Place.objects.filter(nearby_places_ids__contains=[1])
<QuerySet [<Place: Hostel DIC>]>
models.Place.objects.filter(nearby_places_ids__contains=[1,2,3,4])
<QuerySet []>
1 Comment
Timofey Borisov
SQLite does not support this Field
(only for Django with Postgres DB)
You can use ArrayField with base_field IntegerField
A field for storing lists of data. Most field types can be used, and you pass another field instance as the base_field. You may also specify a size. ArrayField can be nested to store multi-dimensional arrays.
ArrayField(
models.IntegerField(),
blank=True, # Optional: allows the array to be empty
default=list # Default value is an empty list
)
From 2018
CommaSeparatedIntergerField is no more available since Django 1.9:
Deprecated since version 1.9: This field is deprecated in favor of
CharFieldwith validators=[validate_comma_separated_integer_list].
By default it sets a comma separated integer list field.
Returns a RegexValidator instance that ensures a string consists of integers separated by sep. It allows negative integers when allow_negative is True.
from django.db import models
from django.core.validators import int_list_validator
class YourModel(models.Model):
....
....
int_list = models.CharField(validators=int_list_validator)
....
1 Comment
msampaio
It should be something like
models.CharField(validators=[int_list_validator], max_length=100)CommaSeparatedIntegerField comes to mind instantly. It is implemented as VARCHAR on most database backends. To be sure though, you may want to skim through django/db/backends/*.
2 Comments
Christian
That basically means that I have to convert the string back into integers myself?
VertigoRay
This is super dated information. The current dev (nor the current release: v1.11) site that you linked, doesn't mention a CommaSeparatedIntegerField.
See this answer for a description of a possible alternative version of CommaSeparatedIntegerField that would do more of the work for you (converting from list to string and back). Maybe you could check in with that guy about whether he wrote it already :-)
Comments
If you're using PostgreSQL, you can store array types natively.
See for example: https://github.com/aino/django-arrayfields and https://github.com/ecometrica/django-dbarray
Comments
Use ArrayField . Here's the syntax :
from django.contrib.postgres.fields import ArrayField
class SampleModel(models.Model):
my_integer_array = ArrayField(
models.IntegerField(),
default= [1,1,0,0], blank=False,null = False, size = 4)
To store a complete array :
SampleModel.my_integer_array = [3,4,5,6]
SampleModel.save()
To store/update a single element :
SampleModel.my_integer_array[2] =7
SampleModel.save()
To fetch the entire array :
my_variable = SampleModel.my_integer_array
To fetch a single element :
e = SampleModel.my_integer_array[3]
Note : ArrayField can only be used when you are using postgreSQL as the database
