Copy a model to another database in symfony 1.4

Using Symfony 1.4 and doctrine I'd like to save a retrieved model to a different database connection:

retrieve model from master-database
change database connection to slave-database
save the model to the slave-database

I have the 2 connections defined in databases.yml. here in pseudo-code:

$model = [retrieved from master-database];
$slaveConnection = Doctrine_Manager::getInstance()
    ->getConnection('slave-connection');
$model->save($slaveConnection);

If I create a new model, $model=new model(); the "code" above successfully saves the model to the slave-connection.

What is going wrong? According to the Symfony log, Symfony recognizes the model as existing and issues an update (instead of an insert).

UPDATE model SET updated_at = '2011-10-21 17:37:32' WHERE id = '1';

Although Symfony is using the correct database connection ('slave-connection'), the update fails because the model isn't present in the slave-database, yet.

And the insert into the slave-database should use all values of the model, not only the changed ones, too.

Anyone can point me to the right direction to save an existing model to a different database?

edit with my solution.

Thanks samura!

Just some additions: After performing deep copy Symfony saved a new id. But I wanted to really clone the model object to the slave db and so, I had to modify the id. That caused unique constraint exceptions, so I had to delete first. So this is it:

$id = $model->getId();
$slaveConnection->execute("delete from modeltable where id=".$id);
$model_copy = $model->copy(true); # deep copy
$model_copy->setId($id);
$model_copy->save($slaveConnection);

hope this helps if someone else stumbles.

Solution

You could use the public function copy($deep = false) method of the Doctrine_Record class.

$model = [retrieved from master-database];
$slaveConnection = Doctrine_Manager::getInstance()
  ->getConnection('slave-connection');
$model_copy = $model->copy(true); # deep copy
$model_copy->save($slaveConnection);