Hi, On Wed, Nov 30, 2011 at 3:21 PM, Michael Dürig <[email protected]> wrote: > 1) Does visible mean immediately visible on next access or visible after > refresh? The second case would work with snapshot isolation.
That's up the implementation. Section 10.11.1 of JSR 283 [1] explicitly allows changes to become visible only after a refresh: "[...] items that do not have changes pending have their state refreshed to reflect the current persisted state, thus revealing changes made by other sessions." More generally about the write skew -issue; I don't think that's a common problem in practice. There aren't too many clients that explicitly interleave operations of multiple sessions within a single thread. And in a multithreaded setup a client would even with Jackrabbit 2.x need to use explicit synchronization to enforce more complex content constraints. [1] http://www.day.com/specs/jcr/2.0/10_Writing.html#10.11.1%20Refresh BR, Jukka Zitting
