It would be nice to be able to notify script that some data may have been lost due to disk corruption or other failure.
This was discussed some in [thread], with the leading idea being an attribute on the upgradeneeded and success events that are fired at open requests. The attribute's could be called "dataLoss" with values including "none", "total", or "partial".
The chrome implementation has been started, see [chromebug].
Marking RESOLVED LATER to denote that it should be considered for V2, not V1.
We have heard from web application developers that they want even more transparency into what is causing data loss. Chrome is going to ship a dataLossMessage alongside dataLoss on the upgradeneeded event, as described in this thread:
As dgrogan@ noted, we shipped IDBVersionChangeEvent#dataLoss and IDBVersionChangeEvent#dataLossMessage in Chrome, and it's seeing use. Since they're not widely publicized entry points we're open to alternate suggestions.