PHP, clues on how to find this function

[MeF1sT]

I'm editing a WordPress plugin and I'm creating new models and functions to create order templates. My PHP is a little rusty since I haven't been doing a lot of PHP work for the last couple of years. So I have been able to track where all the calls I need are, but I can't find this particular function, which makes me think that probably is a PHP function rather than a function built-in within the app. I don't know all there is to know about OOP in PHP.I have this call, but it doesn't seem to insert anything into the database, if this is a PHP way of inserting rows, how can I check for errors?\[code\]$this->_db->insert('wp_3_cart66_template_orders', $order_info_copy);$this->id = $this->_db->insert_id;\[/code\]I also find this abstract class that a lot of other classes seem to inherit from and it contains this function...\[code\]protected function _insert() {if(isset($this->_data['created_at'])) { $this->_data['created_at'] = date('Y-m-d H:i:s', Cart66Common::localTs());}if(isset($this->_data['updated_at'])) { $this->_data['updated_at'] = date('Y-m-d H:i:s', Cart66Common::localTs());}$this->_db->insert($this->_tableName, $this->_data);$this->id = $this->_db->insert_id;return $this->id;\[/code\]}I don't think it's calling that protected function because I tried to output something from inside the function and then \[code\]exit();\[/code\] but it seems it was ignored.