Django Training

⚠️ This material is archived and will not receive further updates. For the latest information on Django's ORM, it is advised to look at the available framework documentation.

Master the Django ORM for fun and profit, by actually writing code.

All web apps need to persist and retrieve data to be useful. You can use Django-ORM to access and update your persisted data. The business of retrieving and storing data can be done in multiple ways; some better than others.

To get familiar with the Django ORM, start by reading through https://docs.djangoproject.com/en/2.2/topics/db/optimization/. This project is a training module containing exercises that help solidify the learnings.

What is Django?

Django is a popular Python framework for building web applications. You can learn more about Django on its website. Django comes with baked-in support for things like handling API requests and persisting Python model objects to the database. Django provides a full-featured ORM (Object Relational Mapper) to facilitate persistence to relational databases via a Python API -- that's right, no SQL required.

The Django ORM has its pros and cons. Whether or not you like it is one question, but if you find yourself having to work with it, it's very important to understand how it works:

• How do I minimize the number of database queries I make?
• When do my querysets get evaluated?
• What does the generated SQL look like?

These are just some of the questions that are important to answer to work effectively with Django.

What is django-training?

This project aims to get you familiar with the Django ORM by going through a set of exercises. Each exercise gets you to try and minimize the number of queries made in each scenario.

To go through the exercises:

• Clone this repo: git clone [email protected]:tophat/django-training.git
• Run . script/bootstrap to initialize dependencies and virtualenv (see more https://github.com/github/scripts-to-rule-them-all)
• Go to one of the exercises, e.g. cd exercise/exercise_1
• Run the test to see what was expected, e.g. inv test --exercise=1 or inv test 1
• Fix the implementation, e.g. goto exercise/exercise_1/use_cases.py
• For a reference to documentation that will help you solve the question use inv test 1 --hint
• Run the test to verify your solution, e.g. inv test 1

Contributing

The following invoke commands are available when contributing to this project:

Command	Description
lint	Lint checks everything, does not reformat files
format	Fixes formatting for all python files

Contributors

Thanks goes to these wonderful people (emoji key):

sjoanes 💻 🤔 📖

Marc Cataford 🚇 📖

Michael Rose 💻 📖 🚇

This project follows the all-contributors specification. Contributions of any kind welcome!