Is there a way to exclude a particular column from being part of the update statement that nhibernate creates? Is it a many to one column that is needed to traverse to get other values but I need to disable it from being written when other values are written.

I think update=false on the property tag will do it.

If you are talking about <many-to-one>, then just make sure that Cascade=None (or any other expect Save/Update).