Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
Is it possible, using an Observer, to observe the creation of JOIN records? For example, you have a User Model that has_and_belongs_to_many Book Models. Is it possible to monitor books_users records as they are created or deleted or must I have a BookUser model to do this?
Example of what I want to observe:
User.books << book OR
User.books.push(book) OR whatever!
Thanks,
Dave K.
This is the exact reason you should be using a has_many :through, instead of has_and_belongs_to; It allows you to create a BookUser model in which regular activerecord callbacks/observers can be used (such as after_save). This site explains the differences better, http://blog.hasmanythrough.com/2006/4/20/many-to-many-dance-off