How to integrate Django with a legacy database¶

Give Django your database parameters¶

You’ll need to tell Django what your database connection parameters are, and what the name of the database is. Do that by editing the DATABASES setting and assigning values to the following keys for the 'default' connection:

• NAME

• ENGINE

• USER

• PASSWORD

• HOST

• PORT

Auto-generate the models¶

Django comes with a utility called inspectdb that can create models by introspecting an existing database. You can view the output by running this command:

$ python manage.py inspectdb

Save this as a file by using standard Unix output redirection:

$ python manage.py inspectdb > models.py

This feature is meant as a shortcut, not as definitive model generation. See the documentation of inspectdb for more information.

Once you’ve cleaned up your models, name the file models.py and put it in the Python package that holds your app. Then add the app to your INSTALLED_APPS setting.

By default, inspectdb creates unmanaged models. That is, managed = False in the model’s Meta class tells Django not to manage each table’s creation, modification, and deletion:

class Person(models.Model):
    id = models.IntegerField(primary_key=True)
    first_name = models.CharField(max_length=70)

    class Meta:
        managed = False
        db_table = "CENSUS_PERSONS"

If you do want to allow Django to manage the table’s lifecycle, you’ll need to change the managed option above to True (or remove it because True is its default value).

Install the core Django tables¶

Next, run the migrate command to install any extra needed database records such as admin permissions and content types:

$ python manage.py migrate

Test and tweak¶

Those are the basic steps – from here you’ll want to tweak the models Django generated until they work the way you’d like. Try accessing your data via the Django database API, and try editing objects via Django’s admin site, and edit the models file accordingly.