interesting to see this forum show-up again.
remember 15 years ago there were posts about DYI drone from some random guy with lots of theoretical physics about stable conditions derivations. it got a lot of criticism. now looking back and following what DJI is doing with sensors, his approach was totally wrong and that community nailed it with feedback. the forum got some extravagant ideas and some worthy criticism. at least back then.
runet sites of that era are often born out of the hacker's characteristic contrarian attitude "because we can". attempts to monetize them in more recent years are bound to accomplish little more than fuck up the content quality and/or the "owner cashes out and opens cafe" thing.
nevertheless, to this day, when i think habrahabr, i think way higher bar for technical competence than hn. it's all in the attitude.
Shortly after, it became hilariously easy to farm and manipulate karma balances across the entire site. With 50 accounts (mults or real people all the same) you could create a new account a day.
Monetization started when it was already in a death spiral.
Rows that need seconds (e.g. bank transactions) are events, they aren't "valid" from a particular point in time forward, they just happen.
I understand how convenient it is to use UTC-only timestamps. It works in most cases but not all.
A 7th normal form should mandate that no identifiers should ever be assigned to identifiers.
I probably wouldn't for country_code specifically, but for most things its useful even when you have a 'natural' key.
Modern data sources increasingly lean towards and produce nested and deeply nested semi-structured datasets (i.e. JSON) that are heavily denormalised and rely on organisation-wide entity ID's rather than system-generated referential integrity ID's (PK and FK ID's). That is a reason why modern data warehouse products (e.g. Redshift) have added extensive support for the nested data processing – because it neither makes sense to flatten/un-nest the nested data nor is it easy to do anyway.