Prod Destruction DBs
Congratulations, production anarchist. You've conquered feature flags and cascading failures. Now we enter the final frontier: the database layer. Here, a single migration can erase years of work. Master these techniques and you'll achieve legendary status.
Welcome to the masterclass. By now, you've earned your stripes breaking APIs and melting down microservices. But let's be honest—those are amateur hour compared to what we're about to explore. Today, we're going deep into the one place where mistakes become permanent: your production database.
Let's start with the crown jewel of database destruction: the irreversible migration. The key here is elegance. Anyone can write DROP TABLE users; and call it a day, but that's crude. No, what you want is a migration that looks reasonable in code review. Something like renaming a column from user_id to userId for "consistency." Bonus points if you forget the data backfill step. Deploy it on a Friday afternoon, and watch as foreign key constraints start screaming across three continents. The beauty? By the time anyone notices, you've already lost the old column data forever.
Next, we have the index-free join apocalypse. This one's subtle and devastating. Find a frequently-queried table with millions of rows—something like order history or user sessions. Now, "optimize" a common query by removing what you think is a "redundant" index. Maybe add a clever join on an unindexed column while you're at it. Deploy during peak traffic hours for maximum impact. As the database starts scanning entire tables for every request, watch your response times climb from milliseconds to minutes. The incident channel will light up like a Christmas tree, and your DB will be gasping for CPU like it just ran a marathon.
But wait, there's more. Let's talk about the n+1 query from hell. This is where you take a perfectly fine bulk query and "refactor" it into individual database calls inside a loop. The trick is to hide it behind an abstraction layer so it's not immediately obvious. Wrap it in some GraphQL resolvers or a fancy ORM pattern, and suddenly every page load triggers 500 database queries instead of one. Combine this with removed indexes from the previous step, and you've essentially created a database DoS attack that passes code review.
For the truly ambitious, there's the timezone-agnostic datetime catastrophe. Start storing datetimes without timezone information, or better yet, mix UTC with local times in the same column. Add some date math that doesn't account for daylight saving time changes. The result? Scheduled jobs that run at random times, reports that are off by hours, and angry customers in every timezone except one. The best part? This bug will resurface twice a year, every year, forever.
Finally, the pièce de résistance: the transaction-free money operation. Find any code that handles financial transactions—payments, refunds, credits, whatever. Now remove the database transaction wrapper because "we're using idempotent APIs now" or "the ORM handles it." Deploy it and wait for the race conditions to emerge. When two processes try to update the same balance simultaneously, you'll get phantom money appearing and disappearing like a quantum physics experiment. The accounting team will be writing off discrepancies for months.
Remember: with great power comes great responsibility. And by responsibility, I mean the ability to create database backups that you'll frantically restore at 3 AM while your phone melts from Slack notifications. But hey, that's the price of mastery.
Now go forth and leave no schema unbroken. You've earned this.
