refs

https://stackoverflow.com/questions/8655909/whats-the-best-way-to-identify-hidden-characters-in-the-result-of-a-query-in-sq

原理先生成一個不可見字元表，而後用表關聯後以不可見字元為關鍵字，查詢表。

--SELECT * from by_dtu WHERE DATALENGTH(bianhao) > LEN(bianhao)

;WITH cte AS
(
   SELECT 1 AS CharCode
   UNION ALL
   SELECT CharCode + 1 FROM cte WHERE CharCode <47 and CharCode!=37
)
SELECT   * FROM   by_dtu T     cross join cte
WHERE
   EXISTS (SELECT *
        FROM by_dtu Tx
        WHERE Tx.id = T.id
             AND
 

-- 過濾掉% 因為它是個萬用字元
--              Tx.bianhao LIKE '%' + CHAR(cte.CharCode)  + '%'
              Tx.bianhao LIKE '%' + (select case when cte.CharCode=37 then '\'+CHAR(cte.CharCode) else CHAR(cte.CharCode) end ) + '%'
						 
         )