Comment by mythoughtsexact
2 days ago
I keep seeing this crap ass design where developers or some product a-hole decides their schema for users needs a field in their table where it shows the last_login_time. It's a shit design, it does not scale, nor is it necessary at all to get that one piece of information.
Use a damned log/journal table if you absolutely must, but make sure it's a fire away and forget non-transactional insert because you morons keep writing software that requires locking the whole users table and that causes huge performance issues.
Your rant is mostly valid except for one thing: most DBMS systems don’t lock the whole table for a point update. Almost all of them will take a short lived row lock only.