Building a Toy Database: Concurrency is Hard
Building a Toy Database: Learning by Doing
Ever wondered how databases work under the hood? I decided to find out by building one from scratch. Meet Bazoola - a simple file-based database written in pure Python.
Why Build a Toy Database?
As a developer, I use relational databases every day, but I never truly understood what happens when I INSERT or SELECT. Building a database from scratch taught me more about data structures, file I/O, and system design than any tutorial ever could.
Plus, it's fun to implement something that seems like magic!
Read moreThe Cartesian Product Trap in Django ORM
I hit a performance wall at work recently after adding a single extra Count() on a Django queryset that looked harmless. Luckily, the problematic code didn't make it into the production environment, but I had to think hard to figure out what went wrong and find a solution.
The Hidden Cost of Test Inheritance
I'm subscribed to Adam Johnson's blog and usually really enjoy his writing - it's practical, deep, and no-bullshit. But one recent post, Python: sharing common tests in unittest, caught me off guard.
It describes a "neat" pattern: write reusable test logic in a base class, subclass it to test multiple objects, hiding the base class from unittest discovery. While the intent is fine - DRYing out duplicated test code - the result is fragile, confusing, and just not worth it.
Here's why.
Read moreWhy Django's override_settings Sometimes Fails (and How reload + patch Saved Me)
Sometimes @override_settings just doesn’t cut it.
I ran into a nasty issue while testing a Django module that relies on global state initialized during import. The usual test approach didn’t work. Here’s what happened and how I solved it.
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