djorm-ext-pgarray 0.10

Introduction

Django by default, has a large collection of possible types that can be used to define the model. But sometimes we need to use some more complex types offered by PostgreSQL. In this case, we will look the integrating of PostgreSQL array with Django.

Quickstart

djorm-ext-pgarray exposes a simple django model field djorm_pgarray.fields.ArrayField. This accepts two additional parameters: dbtype that represents a postgresql type, and dimension that represents a dimension of array field.

This is a sample definition of model using a ArrayField:

from django.db import models
from djorm_pgarray.fields import ArrayField
from djorm_expressions.models import ExpressionManager

class Register(models.Model):
    name = models.CharField(max_length=200)
    points = ArrayField(dbtype="int")
    objects = ExpressionManager()

class Register2(models.Model):
    name = models.CharField(max_length=200)
    texts = ArrayField(dbtype="text", dimension=2) # this creates `points text[][]` postgresql field.
    objects = ExpressionManager()

>>> Register.objects.create(points = [1,2,3,4])
<Register: Register object>
>>> Register2.objects.create(texts = [['Hello', 'World'], ['Hola', 'Mundo']])
<Register2: Register2 object>

class Register(models.Model):
    name = models.CharField(max_length=200)
    macs = ArrayField(dbtype="macaddr", type_cast=lambda x: str(x))
    # Same as previous line but uses str as callback directly
    # macs = ArrayField(dbtype="macaddr", type_cast=str)
    objects = ExpressionManager()

How install it?

You can clone the repo from github and install with simple python setup.py install command. Or use a pip, for install it from Python Package Index.

pip install djorm-ext-pgarray

Additionally, you can install djorm-ext-expressions, that can help with complex queries using array fields.

Known issues

• Querysets using expressions package can not be used as subqueries. Because alias propagation is not working properly.