I have a form for Library, which has several nested objects for Librarian. My question is:
How can I validate uniqueness of Librarian's name? (there may be multiple librarians for one library, but there should not be the same librarian appears twice). I found a hint but couldn't make it work:
validates_uniqueness_of :task_name, :scope => :project_id
Please give me an example, because I found pieces to the puzzle but have not been able to put them together.
If Librarian
has library_id
:
validates_uniqueness_of :name, :scope => :library_id