Q: Where can I find documentation for NHibernate ISession.Persist()? NHibernate's ISession exposes a method Persist() with two overloads. I cannot find documentation on this method anywhere. It's not even mentioned in the NHibernate reference material on http://nhibernate.info/doc/nh/en/index.html.
Is this method deprecated, or will it be? When is it supposed to be used? How does it compare to SaveOrUpdate()?
Any pointers would be much appreciated.

A: The last comment on this thread http://opensource.atlassian.com/projects/hibernate/browse/HHH-1273 specifies it very well:

persist() is well defined. It makes a
  transient instance persistent.
  However, it doesn't guarantee that the
  identifier value will be assigned to
  the persistent instance immediately,
  the assignment might happen at flush
  time. The spec doesn't say that, which
  is the problem I have with persist().
persist() also guarantees that it will
  not execute an INSERT statement if it
  is called outside of transaction
  boundaries. This is useful in
  long-running conversations with an
  extended Session/persistence context.
A method like persist() is required.
save() does not guarantee the same, it
  returns an identifier, and if an
  INSERT has to be executed to get the
  identifier (e.g. "identity" generator,
  not "sequence"), this INSERT happens
  immediately, no matter if you are
  inside or outside of a transaction.
  This is not good in a long-running
  conversation with an extended
  Session/persistence context.

Also it seems from what I could gather from other sources that an entity having cascade="persist" will cascade at the time of the call, not on flush. That might very useful too.
