The first one is correct. On Tue, Sep 14, 2010 at 3:22 PM, peter veentjer <alarmnum...@gmail.com>wrote:
> I have got a question about the Clojure ensure and how it actually > works and the documentation doesn't provide enough information. > > I see a few different solutions: > > 1) An optimistic approach: Once a ref is 'ensured' it is included in > the conflict detection set. This means that the approach is still > completely optimistic because 2 concurrent transactions that have the > same ensured ref, one of them is going to fail when the transaction > wants to commit. This is a commit time ensure. > > 2) The other approach is a more pessimistic approach where a ref can > be protected against writes made by other transaction as soon as it is > ensured. It still allows reads to happen, but a write/ensure is going > to fail. It could be compared to a oracle 'select.. for update'. This > is an encounter time ensure. > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en