> 2. Do people [on any stack] bother to cache query results as a matter of course?

I do it (Firebird+.NET). The site is mostly read only (and the data can be minutes stale). It saves me CPU (which I pay on cloud) and gives me ~100ms responses instead of <1s. Not a huge difference, but you can feel it's fast fast.

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Mgr. Jiří Činčura
Independent IT Specialist