ActiveRecord has_and_belongs_to_many doesn't include self.table_name_prefix

Hi Neeraj,

Thanks for your response, here is the extract from schema.rb related to user and group, note that schema.rb was built with rake db:schema:dump.

create_table "t_sys_groups", :force => true do |t|

t.string   "name",            :limit => 50,  :null => false
t.string   "description",     :limit => 250
t.string   "sysCreatedBy",    :limit => 20,  :null => false
t.datetime "sysDateCreated",                 :null => false
t.string   "sysModifiedBy",   :limit => 20
t.datetime "sysDateModified"
t.integer  "sysVersion"

end

add_index "t_sys_groups", ["name"], :name => "xname", :unique => true

create_table "t_sys_groups_users", :id => false, :force => true do |t|

t.integer "group_id", :null => false
t.integer "user_id",  :null => false

end

add_index "t_sys_groups_users", ["group_id", "user_id"], :name => "groupId", :unique => true add_index "t_sys_groups_users", ["group_id"], :name => "FKC3322168779D6A1C" add_index "t_sys_groups_users", ["user_id"], :name => "FKC33221685DE005CE"

create_table "t_sys_users", :force => true do |t|

t.string   "name",            :limit => 50, :null => false
t.string   "password",        :limit => 20, :null => false
t.date     "startDate"
t.boolean  "active",                        :null => false
t.string   "sysCreatedBy",    :limit => 20, :null => false
t.datetime "sysDateCreated",                :null => false
t.string   "sysModifiedBy",   :limit => 20
t.datetime "sysDateModified"
t.integer  "sysVersion"

end

add_index "t_sys_users", ["name"], :name => "xname", :unique => true

Then the models are:

User (located in models/system/user):

class System::User < ActiveRecord::Base

has_and_belongs_to_many :groups
validates_presence_of :name, :password, :active

end

Group (located in models/system/group):

class System::Group < ActiveRecord::Base

has_and_belongs_to_many :users
validates_presence_of :name

end

And Finally system.rb (located in models):

module System

def self.table_name_prefix
  't_sys_'
end

end

Hope these code will helps...

Thanks,
juan77.-

Currently habtm doesn't take into account the namespaces for computing the join table like the other associations.

See #4975 Model Namespaces and HABTM for related which would suggest the code has to be changed to support namespaces like the other associations.

Currently habtm doesn't take into account the namespaces for computing the join table like the other associations.

Samuel, i told you before, namespaces doent go into the table_name and this is the expected behaviour. As rdoc says:

Nested classes are given table names prefixed by the singular form of the parent‘s table name. Enclosing modules are not considered.

@juan this is no bug the join_table for habtm does not respect the tablename prefix cause habtm does not use the tablenames of the joined classes.

as described in rdoc:

Unless the join table is explicitly specified as an option, it is guessed using the lexical order of the class names.

if you want your jointable other than this you have to specifiy it.

I understand that you and Samuel arent happy with this, and really neither am i.
i had a discussion about namespaces going into the tablename with koz some time ago. i think this matter should be addressed in a different way. maybe a discussion about this in the mailinglist.
Discussing this in a kinda bugreport like ticket with a constricted view on the issue only addressing habtm, will not help much.

I could imagine modifing habtm to use the table_names and not the class_names would be better and more like what the user expects. This could be handled without talking about namespaces at all, but even there we need a discussion if the two tablenames should be simply concated or if there should be some mechanism so the prefix is only used once and so on.

Hi Samuel & Kane,

Now understand a bit more the discussions you have, I respect your opinions and now use :join_table to acomplish my requirements and works great. My humildy opinion is that if these two models belongs to the same namespace I expected as a common behaviour to include the same namespace prefix. For me if one person uses namespaces for models I interpret that all the models belogns usually to at least one namespace, and if two modules has different namespace would be "my_model_with_namespace_has_the_other_model_with_namespace."

So my idea is if I have four models like: admin/user, admin/group, hr/role and system I expect:
admin_groups_has_users (because belogns to same namespace, and groups frist because of letter g)
admin_groups_has_hr_roles (different namespaces)
admin_users_has_hr_roles (start admin, because a is first than h).
systems_has_admin_groups (system hasn't namespaces, so be first).

Of course we can remove 'has", but I think that helps to be more understandable, and if the users don't like anything of these they have always :join_table.

These are some ideas you I can contribute to the debacle :P

thanks,
juan77

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