ActiveRecord and working with sequences

Howdy,

(sorry if this ends up as a duplicate post, my subscription was messed up)

I'm very new with ruby and ActiveRecord.

I've got a table in postgres that looks something like

create table test
    test_id       not null default nextval('test_id_seq')
    test_parent   int not null
    test_name     varchar(20) not null


For the parent record, test_parent = test_id.
I can't change the schema, so i need to work with the table structure I 
have.


What's the best way to handle that situation in ActiveRecord?

It seems like i should do something like:
SEQ = <code to select nextval('test_id_seq')>
Test.new(:test_id => SEQ, :test_parent => SEQ, :test_name => 'woohoo' );


I'm not sure how to active the <code to select nextval()> portion with 
ActiveRecord.

I tried:
seq = ActiveRecord::Base.connection.execute("SELECTnextval('test_id_seq')")

And that seems to be doable, but the PG:Result class is a little weird, 
so I was hoping there was a better way.


Thanks.

Dave