Has_and_belongs_to_many refer to same Model

Rails
1

I have a User model and in I want to have a

has_and_belongs_to_many :users

Obviously that won’t work since the join table will have the same column
names (user_id).

What approach should I take?

thanks

2

On Mon, Aug 24, 2009 at 6:24 PM, Allen
Walker[email protected] wrote:

I have a User model and in I want to have a

has_and_belongs_to_many :users

Obviously that won’t work since the join table will have the same column
names (user_id).

What approach should I take?

You need to give the association a different name, and a few other
things

class User
has_and_belongs_to_many :friends,
:class => “User”,
:association_foreign_key =>
“friend_id”,
:join_table =>
“friends_users”
end

You then need to make a join table named “friends_users” with no
primary key and user_id and friend_id columns.

–
Rick DeNatale

Blog: http://talklikeaduck.denhaven2.com/
Twitter: http://twitter.com/RickDeNatale
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3

Thanks. one thing I noticed is that it’s “:class_name” not just “:class”
(2.3.3)

Rick Denatale wrote:

You need to give the association a different name, and a few other
things

class User
has_and_belongs_to_many :friends,
:class => “User”,
:association_foreign_key =>
“friend_id”,
:join_table =>
“friends_users”
end

You then need to make a join table named “friends_users” with no
primary key and user_id and friend_id columns.