Handling updates

[Oak Norton]

OK, another newbie question.  Once you install a program on someone's local
machine for win/linux/mac that uses mysql or PG, do you typically notify
them of patches to the engine or expect end users to be smart enough to go
out and get the patches themselves?  It doesn't seem likely that most end
users would have any clue how to do this.  So if I have a robust application
that uses one of these databases, are people required to patch, or since
it's a local install can you just toss a database file out there that will
respond to sql queries like an access database where it's essentially just a
file? (I don't suppose there's a hack to let access databases run on
Mac/Linux???)

Thanks,

Oak