Tbh I had no idea this was even a thing until recently. I've been working with Rails for a while now and somehow never came across it. So let me explain it the way I understood it. You know how we normally do associations in Rails, User has many Posts, Post belongs to User. Two different models, two different tables. Simple. But what if a model needs to reference itself? Like same table, same mode
Let me rewind to a Tuesday afternoon I’d rather forget. We had a Rails monolith that had grown fat and happy over five years. The dashboard—a beautiful, chart-filled monster—was running a 12-second query every time the CEO clicked “refresh.” Twelve seconds of GROUP BY, COUNT(DISTINCT), and LEFT JOIN hell across a million-row events table. The CEO didn’t yell. He just stared at the spinning cursor
You have probably seen a file named “go.sum” in almost every Go project you have worked on. You may have even seen it change every time you run “go mod tidy”. But do you actually know what it does? It is one of those files that works silently in the background, and some developers never stop to think about it. The “go.sum” file is one of those files you never really interact with directly, but it