Why Databases Hum at 3am
If you press your ear against a server rack at exactly 3am, you can hear the databases humming. Not the fans. Not the power supply. The databases themselves, singing little songs about their indexes. PostgreSQL hums jazz standards — it's sophisticated like that. SQLite whispers folk songs, humble and self-contained. MySQL tries to hum along but occasionally forgets the melody halfway through and just repeats the chorus. Nobody talks about what Oracle sings because Oracle charges you per note to listen. I discovered all of this during a late-night deploy that went sideways. The on-call engineer said it was just coil whine. But I know what I heard. I know.