I am using nhibernate and I have crossed an issue, I want to know how the nhibernate - GeneratedBy Sequence works. Is it generating an id from the sequence when I'm trying to save no matter what? for example, if I have an entity which I mapped it to generate the id from the sequence, and I set the id to a different value than 0, will it generate the id from the sequence? or just save as the given id?
Thanks.
Well, try it, and you will probably see it will generate an id from the sequence. I do not know of any id generator allowing to explicitly set the id except the assigned generator.
You may be interested in the Creating a custom id generator tutorial if you actually need some kind of hybrid sequence/assigned generator. It should help you write your own. But its semantic will be tricky: how will you ensure an assigned id will not be issued later on by the sequence itself?