> PostgreSQL requires opening a separate connection, Redis lacks it entirely, and I think both Mongo and MySQL lack it entirely.
MySQL has a kill command, which does need to be done on another connection (might also need more permissions, it's been a while). It's been a while since I used a lot of MySQL, but this was definitely a pain point when things went sideways.
Re:Don't trust default timeouts
by jd_mongodb on Saturday August 29, 2020 @01:33PM
(#24317807)
MongoDB has killOp which will allow a user to kill any operation they have an operation ID for:
As for "if the requester goes away", remember that the requester might be a few hops away. E.g., the HTTP connection from the mobile client drops; the web server and its connection to the DB is still alive and well. I can forcefully shut that connection, but that's somewhat of a drag (I'd rather keep it open, since it is perfectly good).
Beyond closing the connection, and being able to issue some form of "cancel this query" request: HTTP/1 lacks it entirely, PostgreSQL requires opening a separate connection, Redis lacks it entirely, and I think both Mongo and MySQL lack it entirely.
Even support for "time this request out" is spotty.