Dependent nullify doesn't use save?

If you have a model that has

has_many :clients, :dependent => :nullify

Will that run the save method for each client or will it just simply
nullify the foreign key using straight SQL without every calling
save. Because I have some very important before_save code in my
Client model and I do not think it is getting ran.

Thanks for your help.

Thank You,
Ben J.
E: [email protected]