protected function _getTokenFromSqlWhere($from, $fieldName)
    {
        $lsDb = $this->getSourceDatabase();
        $tokField = $lsDb->quoteIdentifier($fieldName);

        foreach (str_split($from) as $check) {
            $checks[] = 'LOCATE(' . $lsDb->quote($check) . ', ' . $tokField . ')';
        }

        return '(' . implode(' OR ', $checks) . ')';
    }