http://codeigniter.com/forums/viewthread/46694/
The problem with the models userguide section is that it suggests to pass $this to the update, however when you pass this you are also passing _ci_scaffolding to the insert, as extending from model includes these values for scaffoliding.
so do not pass $this to any active record functions, it is bad practice
documentation example
function update_entry()
{
// yuck yuck as this->_ci_scaffolding will exist and try to insert/update
// it into the database as a column name.
$this->title = $_POST['title'];
$this->content = $_POST['content'];
$this->date = time();
$this->db->update('entries', $this, array('id', $_POST['id']));
}
SO instead of doing the above you can do
function update_entry()
{
$data = array(
'title' => $_POST['title'],
'content' => $_POST['content'],
);
$this->db->where('id', $_POST['id']);
$this->db->update('entries', $data);
}
