Ruby on Rails -- has_and_belongs_to_many relationship

I am currently using a legacy database and I have 2 models: submission and publication.

class Submission < ActiveRecord::Base
has_and_belongs_to_many :publications,  :join_table => "ish_sub_pub", :association_foreign_key => "SLN_PUB_FK"
end

class Publication < ActiveRecord::Base

has_and_belongs_to_many :submissions,  :join_开发者_StackOverflowtable => "ish_sub_pub" ,
:association_foreign_key => "SLN_SUBMISSION_FK"

end

When i create a new submission, i want to be able to associate a publication to it and for this i will need to add a new record in the join table, 'ish_sub_pub'.

I am a bit confused about how to proceed with adding a publication to a submission.

Thanks a lot for your help

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Assuming your publication is already instantiated in my_publication, all you need to do is just_created_submission << my_publication.