Transactions in codeigniter with multiple tables

I'm new to transactions in general, but especially with CodeIgniter. I'm using InnoDB and everything, but my transactions aren't rolling back when I want them to. Here's my code (slightly simplified).

            $dog_db = $this->load->database('dog', true);
            $dog_db->trans_begin();

            $dog_id = $this->dogs->insert($new_dog); //Gets primary key of insert
            if(!$dog_id)
            {
                $dog_db->trans_rollback();
                throw new Exception('We have had an error trying to add this dog.  Please go back and try again.');
            }

            $new_review['dog_id'] = $dog_id;
            $new_review['user_id'] = $user_id;
            $new_review['date_added'] = time();

            if(!$this->reviews->insert($new_review)) //If the insert fails
            {
                $dog_db->trans_rollback();
                throw new Exception('We开发者_如何学C have had an error trying to add this dog.  Please go back and try again.');
            }

                //ADD DESCRIPTION
            $new_description['description'] = $add_dog['description'];
            $new_description['dog_id'] = $dog_id;
            $new_description['user_id'] = $user_id;
            $new_description['date_added'] = time();

            if(!$this->descriptions->insert($new_description))
            {
                $dog_db->trans_rollback();
                throw new Exception('We have had an error trying to add this dog.  Please go back and try again.');
            }

                $dog_db->trans_rollback();  //THIS IS JUST TO SEE IF IT WORKS
                throw new Exception('We have had an error trying to add this dog.  Please go back and try again.');

            $dog_db->trans_commit();
}

catch(Exception $e)
{
    echo $e->getMessage();
}

I'm not getting any error messages, but it's not rolling back either. It should roll back at that final trans_rollback right before the commit. My models are all on the "dog" database, so I think that the transaction would carry into the models' functions. Maybe you just can't use models like this. Any help would be greatly appreciated! Thanks!

Well, I know this post is antique, but here's my 2 cents:

I don't think this:

if(!$this->descriptions->insert($new_description))

will work, cause the insert function from CI active record always returns TRUE (succeeding or not). If you are using debug mode, CI will stop on error and throw a screen message to the user, but insert function will still returns TRUE.

So, if you're willing to control transactions "manualy" with CI, you'll have to use something like this:

...

$this->db->trans_begin();

$this->db->insert('FOO');

if ($this->db->trans_status() === FALSE){

    $this->db->trans_rollback();

}else{

    $this->db->trans_commit();

}

Hope this helps someone...sometime....somewhere

Maybe, it's because you connected using $dog_db, and rolling back nonexisting $booze_db transaction ?(or it's a typo?)