Rails - Mar 2006 - Is there a way to persist a Hash in ActiveRecord?

I can''t seem to figure out a way to persist a hash attribute in 
ActiveRecord. Let''s say I have a Game, which has a many-to-many with 
players.

Each player has an index, but the array can have empty spaces in it 
(since a game might not be filled up yet).

I''d like to model this using a hash, with position --> player
mapping.

(What I don''t want to do is create a "nil" player).

In Hibernate, you would do this with <map>... is there an ActiveRecord 
equivalent?

Thanks,
Dave

-- 
Posted via http://www.ruby-forum.com/.

On 3/26/06, David Tashima <tash@speakeasy.net>
wrote:
>
> I can''t seem to figure out a way to persist a hash attribute in
> ActiveRecord. Let''s say I have a Game, which has a many-to-many
with
> players.
>
> Each player has an index, but the array can have empty spaces in it
> (since a game might not be filled up yet).
>
> I''d like to model this using a hash, with position --> player
mapping.
>
> (What I don''t want to do is create a "nil" player).
>
> In Hibernate, you would do this with <map>... is there an
ActiveRecord
> equivalent?
>
> Thanks,
> Dave
>
It should ''just work'', by converting the Hash to YAML, if you
assign
it to an attribute that maps to a varchar/CLOB column.
If that doesn''t work because I''m crazy and misremembering
something,
you could do it ''manually'' by calling to_yaml on your Hash as
part of
the before_save callback.

I remember that there''s a case statement somewhere in the ActiveRecord
code that decides what to do with an attribute based on its Ruby
type.. and the "else" branch converts it to YAML.