Database migration in production in Django - Mini Project: Build & Apply

Database migration in production

📖 Scenario: You are working on a Django web application that is live in production. You need to add a new field to an existing model and safely migrate the database without downtime or data loss.

🎯 Goal: Learn how to create a new field in a Django model, generate and apply migrations, and handle the migration process carefully in a production environment.

📋 What You'll Learn

Create a new field in an existing Django model

Generate a migration file using Django management commands

Apply the migration to the production database

Ensure the migration is safe and does not cause downtime

💡 Why This Matters

🌍 Real World

Adding new features or fixing bugs often requires changing the database schema in live Django applications without causing downtime or data loss.

💼 Career

Database migration skills are essential for backend developers and DevOps engineers working with Django in production environments.

1

Add a new field to the Django model

Open the models.py file in your Django app and add a new field called is_active of type models.BooleanField with default value True to the existing UserProfile model.

Django

from django.db import models

class UserProfile(models.Model):
    username = models.CharField(max_length=150)
    email = models.EmailField()
    # Add the is_active BooleanField with default True below
    # Your code here

Need a hint?

Use is_active = models.BooleanField(default=True) inside the UserProfile class.

2

Generate the migration file

Run the Django management command python manage.py makemigrations to create a migration file for the new is_active field.

Django

from django.db import models

class UserProfile(models.Model):
    username = models.CharField(max_length=150)
    email = models.EmailField()
    is_active = models.BooleanField(default=True)

# Run the command below in your terminal
# Your code here

Need a hint?

Use the exact command python manage.py makemigrations in your terminal to generate migration files.

3

Apply the migration to the production database

Run the Django management command python manage.py migrate to apply the new migration and update the production database schema.

Django

from django.db import models

class UserProfile(models.Model):
    username = models.CharField(max_length=150)
    email = models.EmailField()
    is_active = models.BooleanField(default=True)

# Run in terminal:
# python manage.py makemigrations

# Now apply the migration with the command below
# Your code here

Need a hint?

Use the exact command python manage.py migrate to apply migrations to the database.

4

Ensure safe migration practices

Add a comment in your code reminding to backup the database and test migrations in a staging environment before applying to production.

Django

from django.db import models

class UserProfile(models.Model):
    username = models.CharField(max_length=150)
    email = models.EmailField()
    is_active = models.BooleanField(default=True)

# Run in terminal:
# python manage.py makemigrations
# python manage.py migrate

# Add a comment about safe migration practices below
# Your code here

Need a hint?

Add a clear comment reminding to backup and test migrations before production deployment.