CI_DB_driver::initialize PHP Method

    public function initialize()
    {
        /* If an established connection is available, then there's
         * no need to connect and select the database.
         *
         * Depending on the database driver, conn_id can be either
         * boolean TRUE, a resource or an object.
         */
        if ($this->conn_id) {
            return TRUE;
        }
        // ----------------------------------------------------------------
        // Connect to the database and set the connection ID
        $this->conn_id = $this->db_connect($this->pconnect);
        // No connection resource? Check if there is a failover else throw an error
        if (!$this->conn_id) {
            // Check if there is a failover set
            if (!empty($this->failover) && is_array($this->failover)) {
                // Go over all the failovers
                foreach ($this->failover as $failover) {
                    // Replace the current settings with those of the failover
                    foreach ($failover as $key => $val) {
                        $this->{$key} = $val;
                    }
                    // Try to connect
                    $this->conn_id = $this->db_connect($this->pconnect);
                    // If a connection is made break the foreach loop
                    if ($this->conn_id) {
                        break;
                    }
                }
            }
            // We still don't have a connection?
            if (!$this->conn_id) {
                //				log_message('error', 'Unable to connect to the database');
                if ($this->db_debug) {
                    $this->display_error('db_unable_to_connect');
                }
                return FALSE;
            }
        }
        // Now we set the character set and that's all
        return $this->db_set_charset($this->char_set);
    }