Originally Posted by kovidgoyal
I can think of lots of problems like this caused by concurrent edits. Really the only safe way to support concurrent editing is with row level locking, the way it is done in databases.
Is it possible to have Calibre run in a "read only" mode, so that it didn't attempt to write to the DB? I guess I'm thinking of a scenario where, say, one family member is the one who maintains updating the ebooks in Calibre while the other family members just browse.