This is the basic reason why raw devices where the way to go for decades for use as database devices and are still in use in most installations.

I'm talking about Sybase here. But any database, which shifts the commit responsible to the operating system (without explicit guarantees that committed data is indeed written to disk) may invite you in for a huge and very unpleasant surprise.

If you've not pulled the plug on your users' workstations, the clients should be perfectly capable of retrying the broken transactions when the database comes back up. There can, of course, be constraints that make this impossible, but sloppy coding making it impossible is more common.