I generally agree, but I think there’s a mistake here comparing something like Postgres to hand-rolled code: Postgres has to implement generally safe optimizati

I generally agree, but I think there’s a mistake here comparing something like Postgres to hand-rolled code: Postgres has to implement generally safe optimizations and so cannot take advantage of invariants that cannot be expressed in a way it understands. For a specific task, with well-understood data, I’d expect a typical programmer should be able to outperform Postgres with a bit of effort. The trade-off here is maintenance cost and a lack of flexibility due to specialization. So, IMO, one ought to reach for an SQL database first and then something else to optimize hot paths as determined by a profiler.