Creating relationship between two model instances

Posted by Lowgain on Stack Overflow See other posts from Stack Overflow or by Lowgain
Published on 2010-05-12T03:57:20Z Indexed on 2010/05/12 4:04 UTC
Read the original article Hit count: 231

Filed under:

ruby-on-rails

|

activerecord

|

object-relational-mapping

This is probably pretty simple, but here:

Say I've got two models, Thing and Tag

class Thing < ActiveRecord::Base
    has_and_belongs_to_many :tags
end

class Tag < ActiveRecord::Base
    has_and_belongs_to_many :things
end

And I have an instance of each. I want to link them. Can I do something like:

@thing = Thing.find(1)
@tag = Tag.find(1)

@thing.tags.add(@tag)

If not, what is the best way to do this? Thanks!

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