Forum: Ruby on Rails Column with dynamic db type

Hi,

I have a Question model where the answer to the question can have
multiple db type (integer, string, boolean, ...).

I would like to know if you have a better solution than this one:

Question:
question:string
answer_type:string

AnsweredQuestion:
question_id:integer
answer:text
answer_type:string

Ex: AnsweredQuestion.create(:question => 1, :answer => '5', :answer_type
=> 'Integer')

My problem with this solution is that I can't question is that I can't
question the answered questions where the answer is > 2.

Any better idea?

On 2 May 2012, at 21:25, Greg Ma <lists@ruby-forum.com> wrote:

> Hi,
>
> I have a Question model where the answer to the question can have
> multiple db type (integer, string, boolean, ...).

I've had a similar situation. I'd use STI to have different models for 
different answer types. My repository at 
http://github.com/ihid/super_sti might help. Email me personally if you 
want some help with that repository.

Jeremy Walker
http://www.ihid.co.uk

Jeremy Walker wrote in post #1059314:
> On 2 May 2012, at 21:25, Greg Ma <lists@ruby-forum.com> wrote:
>
>> Hi,
>>
>> I have a Question model where the answer to the question can have
>> multiple db type (integer, string, boolean, ...).
>
> I've had a similar situation. I'd use STI to have different models for
> different answer types. My repository at
> http://github.com/ihid/super_sti might help. Email me personally if you
> want some help with that repository.

Here's a direct and elegant solution: http://www.mongodb.org/
If rigid schema is the problem, then eliminate your dependence on a 
pre-defined schema.

However, the STI solution mentioned above is probably the next best 
approach.