Upgrading - Incremental or All at once?

Good luck! I have also made customization to the system folder, but only one at least.

Added IGNORE to the insert batch, due to the way I import stuff.

PHP Code:

    /**
     * Insert batch statement
     *
     * Generates a platform-specific insert string from the supplied data.
     *
     * @param    string    $table    Table name
     * @param    array    $keys    INSERT keys
     * @param    array    $values    INSERT values
     * @return    string
     */
    protected function _insert_batch($table, $keys, $values)
    {
        return 'INSERT IGNORE INTO '.$table.' ('.implode(', ', $keys).') VALUES '.implode(', ', $values);
    }