how do I save to a database record with the primary key value = 0?

I have a client's database that I am accessing with nHibernate. In one table, they have a primary key which auto-increments starting at 0. I cannot have the client's database changed to a 1 based auto-increment.

When I attempt to save a child record in a table with a foreign key back to this table I receive the following error: "not-null property references a null or transient value". The problem is only found when I save the child of the record that has the 0 primary key value, al开发者_运维百科l other records work fine.

This is the generator for the parent table

and the foreign key relationship map:

Question: how do I save to a database record with the primary key value = 0?

i cant see your mappings but i would try

public ParentMap()
{
    Id(x => x.Id).GeneratedBy.Increment().UnsavedValue(-1);
}

and

public Parent()
{
    Id = -1;
}