Has_many through issues

Rails
1

Hey all,
I have three tables:
groups(id,name)
forums(id,name)
permissions(group_id,forum_id,read_forum,post_replies,post_topics)

now in script/console I do:

forum=Forum.find_first
group=Group.find_first
perm=Permission.create(:read_forum=>0,:post_replies=>0,:post_topics=>0)

then when I do:

group.permissions << perm

I get:

ActiveRecord::StatementInvalid: Mysql::Error: #42S22Unknown column
‘id’ in ‘where clause’: UPDATE permissions SET read_forum = 0,
group_id = 5, post_replies = 0, forum_id = 5, post_topics = 0
WHERE id = 0

any idea what’s wrong?

thanx in advance

Pat

2

Hello Patrick,

I have three tables:
groups(id,name)
forums(id,name)
permissions(group_id,forum_id,read_forum,post_replies,post_topics)

If you’ve got Group has_many :forums, :through => :permissions
and Forum has_many :groups, :through => :permissions

then your permissions table must have an id column.
Your migration should look like this :

create_table :permissions do |t|
t.column :group_id, :integer
t.column :forum_id, :integer
t.column :read_forum, :integer # with some :default => 0 maybe
t.column :post_replies, :integer
t.column :post_topics, :integer
end

now in script/console I do:

forum=Forum.find_first
group=Group.find_first

find :first is less deprecated thant find_first

-- Jean-François.

–
À la renverse.