how to automatically add default columns to all django model tables

Question

I have the following 4 columns which I would like to add to all tables:

• creationname
• creationdate
• revisionname
• revisiondate

currently I do it the following way:

from django.db import models


class Table_1(models.Model):
    column1 = models.CharField(max_length=64)
    column2 = models.CharField(max_length=64)
    creationname = models.CharField(max_length=64)
    creationdate = models.DateTimeField('creation date', auto_now_add=False)
    revisionname = models.CharField(max_length=64)
    revisiondate = models.DateTimeField('revision date', auto_now=False)

class Table_2(models.Model):
    column1 = models.CharField(max_length=64)
    column2 = models.CharField(max_length=64)
    creationname = models.CharField(max_length=64)
    creationdate = models.DateTimeField('creation date', auto_now_add=False)
    revisionname = models.CharField(max_length=64)
    revisiondate = models.DateTimeField('revision date', auto_now=False)

...

class Table_n(models.Model):
    column1 = models.CharField(max_length=64)
    column2 = models.CharField(max_length=64)
    creationname = models.CharField(max_length=64)
    creationdate = models.DateTimeField('creation date', auto_now_add=False)
    revisionname = models.CharField(max_length=64)
    revisiondate = models.DateTimeField('revision date', auto_now=False)

can this be acchieved in an automated way, so the 4 columns are automatically appended to each table?
note: is this also achievable for all tables of a django project not just the tables of a single django app?

in case this is against django design philosophy please let me know as well

Answer 1

You could use an abstract base model and inheritance to do so:

class ModelWithRevisions(models.Model):
    creationname = models.CharField(max_length=64)
    creationdate = models.DateTimeField('creation date', auto_now_add=False)
    revisionname = models.CharField(max_length=64)
    revisiondate = models.DateTimeField('revision date', auto_now=False)

    class Meta:
        abstract = True


class OtherModel(ModelWithRevisions):
    column1 = models.CharField(max_length=64)
    column2 = models.CharField(max_length=64)

---

Note that if you're trying to track the history of your models, or track who changed them last, you might want to look into an existing model auditing package .

Answer 2

Create a base model. Then extend that model.

class BaseTable(models.Model):
    creationname = models.CharField(max_length=64)
    creationdate = models.DateTimeField('creation date', auto_now_add=True)
    revisionname = models.CharField(max_length=64)
    revisiondate = models.DateTimeField('revision date', auto_now=False)

    class Meta:
        abstract = True


class Table1(BaseTable):
     column1 = models.TextField()
     column2 = models.TextField()