How can I store an array of strings in a Django model?

Question

I am building a Django data model and I want to be able to store an array of strings in one of the variables; how can I do that?

e.g.

class myClass(models.Model):
    title = models.CharField(max_length=50)
    stringArr = models.???

Thanks for the help.

Answer 1

You can use some serialization mechanism like JSON. There's a snippet with field definition that could be of some use to you:

http://djangosnippets.org/snippets/1478/ (take a look at the code in the last comment)

With such field you can seamlessly put strings into a list and assign them to such field. The field abstraction will do the rest. The same with reading.

Answer 2

If you are using PostgreSQL or MongoDB(with djongo) you can do this

For PostgreSQL:

from django.contrib.postgres.fields import ArrayField

For MongoDB(with Djongo):

from djongo import models
from django.contrib.postgres.fields import ArrayField

Then

stringArr = ArrayField(models.CharField(max_length=10, blank=True),size=8)

The above works in both cases.

Answer 3

You can use cPickle...

class myClass(models.Model):
    title = models.CharField(max_length=50)
    stringArr = models.TextField()

from cPickle import loads, dumps
data = [ { 'a':'A', 'b':2, 'c':3.0 } ]
obj = Myclass.objects.get(pk=???)
# pickle data into a string-like format
obj.stringArr = dumps(data)
obj.save()
# restore original data
data = loads(obj.stringArr)

Answer 4

I did this for my model and it worked

from django.contrib.postgres.fields import ArrayField
from django.db import models


class Skill(models.Model):
    name = models.CharField(max_length=50)
    skills = ArrayField(models.CharField(max_length=200), blank=True)

To create

Skill.objects.create(name='First name', skills=['thoughts', 'django'])

To Query

Skill.objects.filter(skills__contains=['thoughts'])

You can refer to the django documentation for more help

https://docs.djangoproject.com/en/3.0/ref/contrib/postgres/fields/

I hope this helps

Answer 5

You can use JSONField for such functionality:

from django.db import models
from django.contrib.postgres.fields import JSONField

class TestModel(models.Model):
    title = models.CharField(max_length=100)
    strings = JSONField(default=list, blank=True, null=True)

    def __str__(self):
        return self.title

for example:

In [1]: fruits = ['banana', 'apple', 'orange']                                                                                                                                         

In [2]: TestModel.objects.create(title='my set', strings=fruits)                                                                                                                       
Out[2]: <TestModel: my set>

In [3]: o = TestModel.objects.first()                                                                                                                                                  

In [4]: o.strings                                                                                                                                                                      
Out[4]: ['banana', 'apple', 'orange']