protected function quoteField($field)
    {
        # The odbc sql only uses it's quote strings for renaming fields, not for quoting table/field names
        if ($this->mode == "odbc") {
            return $field;
        }

        $field = trim($field);

        $chars = $this->quoteChars[$this->mode];

        if (is_array($chars)) {
            $from = $chars[0];
            $to = $chars[1];
        } else {
            $from = $chars;
            $to = $chars;
        }

        $quoted = $from . $field . $to;

        return $quoted;
    }