Re: Django ORM: default value from sql query

You can achieve this by setting a callable default value [1] on you field:

class MyModel(models.Model):
    count = models.PositiveIntegerField(default=lambda:MyModel.objects.count())

[1] https://docs.djangoproject.com/en/dev/ref/models/fields/#django.db.models.Field.default
Le mercredi 21 août 2013 18:49:48 UTC-4, Marcin Szamotulski a écrit :

Dear Django users,

I am would like to set a default value on a model's field as a result of
a simple query.  Something that in SQLAlchemy is done like that:
    http://docs.sqlalchemy.org/en/rel_0_7/core/schema.html#sql-expressions

Specifically I want to count some objects in the database and set this
count as the default value.  I know that this can be done in two steps
first find the value then set it, but I would like to have it done
automatically.

Best regards,
Marcin

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