Why Your Database Isn't Slow. Your Cache Is Missing

If you've ever wondered why every backend system you read about has a cache sitting somewhere in the architecture diagram, this is the "why" behind it, explained the way I actually understood it, not the textbook way. The problem: repeated reads that don't need to happen Imagine a database that many users hit to read the exact same piece of data. Not different data, the same data, over and over. Every single one of those reads goes all the way to the database, even though not