Sorry if this is not the right place, but I could not find anywhere more appropriate. I ran into http://dev.rubyonrails.org/ticket/8811 over the past few days, and it's a very nasty bug. The fact is, validates_uniqueness_of and validates_existence_of (at least) do not respect the SQLite3 timeout database configuration, and cause SQLite Database Busy exceptions.
The bug was moved to low priority two years ago, but I don't see how this is low priority. We have background threads with SQLite connections, so the validations must respect the timeout policy. Otherwise the system randomly blows up when trying to create new model instances (since that will trigger validations). It's not that the threats truly horde the database, they are quick running tasks. It's just that a single collision will cause an exception due to the validations not respecting the timeout policy.
At present we are forced to re-write those validations in a safe way.
Thoughts? Thanks for any advice or consideration. http://dev.rubyonrails.org/ticket/8811