NHibernate SchemaUpdate adding existing foreign keys again?

Question

I'm using SchemaUpdate to synchronize my hbms with existing database. Database has recently created based on hbms and is completely up-to-date. But SchemaUpdate generates all foreign key constraints again.

For example suppose you have Student and Teacher. Student has association to Teacher with name ArtTeacher. ArtTeacher is a foreign key from Student to Teacher. Suppose database is up-to-date and currently holde Student, Teacher and their foreign key relation. So HBM and Database are equivalent. Know SchemaUpdate must not do anything but when I see its generated scripts, it re-produce that foreign key again.

Why this happens? Is there any way to avoid it?

Answer 1

The secret is to ensure that you specify names for the foreign keys, or else NHibernate will generate a random name which won't match the existing schema.

(I fished this answer out of the Google Cache of Afshar's blog post).