ActiveRecord Abstract class

Rails
1

Hi, I was trying to create an abstract class and a subclass which
inherit that abstract class.

However, seems like I cannot instantiate the subclass too. Below is my
code:

//abstractclass2.rb
class Abstractclass2 < ActiveRecord::Base
self.abstract_class = true
end

//subclass.rb
class Subclass < Abstractclass2
end

When I test drive it in rails console, I got the following error:

from (irb):1irb(main):002:0> sb = Subclass.new
ActiveRecord::StatementInvalid: Could not find table ‘subclasses’
from
/usr/lib/ruby/gems/1.8/gems/activerecord-3.1.3/lib/active_record/connection_adapters/sqlite_adapter.rb:439:in
table_structure' from /usr/lib/ruby/gems/1.8/gems/activerecord-3.1.3/lib/active_record/connection_adapters/sqlite_adapter.rb:322:in columns’

If I take out “self.abstract_class”, everything works fine (subclass
object is inserted into abstractclass table but abstractclass can be
instantiated → that’s not what I want to…)

Did I miss something here so that I cannot instantiate the subclass?

Thanks,
Kahou

2

On Dec 3, 6:55pm, “kahou l.” [email protected] wrote:

If I take out “self.abstract_class”, everything works fine (subclass
object is inserted into abstractclass table but abstractclass can be
instantiated → that’s not what I want to…)

Did I miss something here so that I cannot instantiate the subclass?

In the setup you’ve described, rails expects the subclass to have its
own table. If you don’t want that, then don’t set abstract_class to
true

Fred