[Rails3 b4] has_and_belongs_to_many (habtm) with string ids don't work

Thanks for the patch, it work well for foreign keys :)

I have a related issue if I add created_at and/or updated_at columns in users_roles table. It's the same problem: AR try to insert "'a date'" instead of "a date".

I am using rails edge and surprisingly I am getting nil for both created_at and updated_at in my join table. Not sure what I am missing.

ActiveRecord::Schema.define(:version => 20100719150531) do

  create_table "countries", :id => false, :force => true do |t|
    t.string "country_id"
    t.string "name"
  end

  create_table "countries_treaties", :id => false, :force => true do |t|
    t.string   "country_id", :null => false
    t.string   "treaty_id",  :null => false
    t.datetime "updated_at"
    t.datetime "created_at"
  end

  create_table "treaties", :id => false, :force => true do |t|
    t.string "treaty_id"
    t.string "name"
  end

end

class Country < ActiveRecord::Base
  set_primary_key :country_id
  has_and_belongs_to_many :treaties

  def self.lab
    Country.delete_all
    Treaty.delete_all
    c = Country.new(:name => 'india')
    c.country_id = 'c1'
    c.save!

    t = Treaty.new(:name => 'peace')
    t.treaty_id = 't1'
    c.treaties << t
    c.save!
    puts Country.first.treaties.inspect

    con = ActiveRecord::Base.connection
    sql = 'select * from countries_treaties'
    records = con.select_rows(sql)
    puts records.inspect
    record = records.last
    puts record.inspect
    puts record[0]
    puts record[1]
    puts record[2]
    puts record[3]
  end

end

class Treaty < ActiveRecord::Base
  set_primary_key :treaty_id

  has_and_belongs_to_many :countries

  def self.lab
  end

end

Country.lab 

ree-1.8.7-2010.01 > Country.lab
  SQL (0.4ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'

  SQL (3.4ms)  DELETE FROM "countries" WHERE 1=1
  SQL (1.8ms)  DELETE FROM "treaties" WHERE 1=1
  SQL (0.4ms)  INSERT INTO "countries" ("country_id", "name") VALUES ('c1', 'india')
  SQL (0.4ms)  INSERT INTO "treaties" ("name", "treaty_id") VALUES ('peace', 't1')
  SQL (0.2ms)  INSERT INTO "countries_treaties" ("country_id", "treaty_id") VALUES ('c1', 't1')
  Country Load (0.5ms)  SELECT "countries".* FROM "countries" LIMIT 1
  Treaty Load (0.3ms)  SELECT * FROM "treaties" INNER JOIN "countries_treaties" ON "treaties".treaty_id = "countries_treaties".treaty_id WHERE ("countries_treaties".country_id = 'c1' )
[#<Treaty treaty_id: "t1", name: "peace">, #<Treaty treaty_id: "t1", name: "peace">, #<Treaty treaty_id: "t1", name: "peace">]
  SQL (0.2ms)  select * from countries_treaties
[["c1", "t1", nil, nil], ["c1", "t1", nil, nil], ["c1", "t1", nil, nil]]
["c1", "t1", nil, nil]
c1
t1
nil
nil

The has_and_belongs_to_many association doesn't store created_at and updated_at because they would be useless since there is no join model to access them. And since they are created and updated only when assigning one model to another, the times would be exactly the same.

A habtm join table row is never updated even when you add the same model to another. A new row is always created.

c.treaties << t
c.treaties << t

would give 2 additional join table rows.

timestamps should always be updated to reduce any element of surprise. Created ticket #5161 timestamp columns do not get update in the HABTM join table to fix that issue.

@Samuel, I would expect c.treaties << t to create two rows unless you specify :uniq in the association.

Besides, it is documented that all columns in the join table are available in the model instance, overwriting the model ones. So if you do post.tags, where posts and tags have a HABTM relationship, the created_at and updated_at fields for each tag object in post.tags will return the created_at and updated_at value in the join table, and not in the tag attribute. This work for all columns and this is the reason you should not have id in join tables (otherwise it would overwrite your model id).

(from [f576d7cf848717384799a9e9669b253ccc94deb5]) Ensure that primary_keys of HABTM records is not double quoted

[#5152 [Rails3 b4] has_and_belongs_to_many (habtm) with string ids don't work state:reslved] http://github.com/rails/rails/commit/f576d7cf848717384799a9e9669b25...