SQLite Error 5: 'database is locked'.

[bitmap]

As far as I know, DB locking on current versions is akin to DB corruption. You may be able to salvage if you have the skills to play with the DB, but this generally means there was an unexpected event while the DB was being written to (e.g., power outage, hard reset). I believe 10.11 is supposed to help with issues like this, but we're still a ways away from seeing a full release.