protected function _getTokenFromToSql($from, $to, $fieldName)
    {
        $lsDb = $this->getSourceDatabase();
        if ($from) {
            // Build the sql statement using recursion
            return 'REPLACE(' .
                $this->_getTokenFromToSql(substr($from, 1), substr($to, 1), $fieldName) . ', ' .
                $lsDb->quote($from[0]) . ', ' .
                $lsDb->quote($to[0]) . ')';
        } else {
            return $lsDb->quoteIdentifier($fieldName);
        }
    }