How do I get ActiveRecord to show the next id (last + 1) in Ruby on Rails?

Question

Is there a compact way with ActiveRecord to query for what id it\'s going to use next if an object was going to be persisted to the database? In SQL, a query like this would

Answer 1

I don't think there's a generic answer to this since you may not want to assume one database over another. Oracle, for example, may assign id's by a sequence or, worse, by a trigger.

As far as other databases are concerned, one may set them up with non sequential or random id allocation.

May I ask what the use case is? Why would you need to anticipate the next id? What does 'next' mean? Relative to when? What about race conditions (multiuser environments)?