durability

Are there databases that bases durability on redundancy and not on persistent storage?

Sorry that the title isn't exactly obvious, but I couldn't word it better. We are right now using a conventional DB (oracle) as our job queue, and these "jobs" are consumed by some number of nodes (machines). So the DB server gets hit by these nodes, and we have to pay a lot for the software and hardware for this database server. N...

How do in-memory databases provide durability?

The title says all, but more specifically, are there any databases that don't require secondary storage (e.g. HDD) to provide durability? Thank you in advance! Note:This is a follow up of my earlier question. ...