關於Select Where In 的排序問題

有很多人不知道SQL裏怎麼按 Select Where In 的內容進行字段排序.

假如SQL語句爲:

Select *

FROM table1

Where (ID IN (3,5,1,4,2))

如果In後面的條件都是數字,那MSSQL排序應該爲

Select *

FROM table1

Where (ID IN (3,5,1,4,2))

ORDER BY CHARINDEX(',' + CONVERT(nvarchar, ID) + ',', ',' + CONVERT(nvarchar, Replace('3,5,1,4,2', ' ','')) + ',')

改進方法,不去處理空格,直接改用空格判斷.可以用來判斷少數有空格的字符條件.

Select *

FROM table1

Where (ID IN (3,5,1,4,2))

ORDER BY PATINDEX('% ' + CONVERT(nvarchar(4000), ID) + ' %', ' ' + CONVERT(nvarchar(4000), Replace('3,5,1,4,2', ',',' , ')) + ' ')

其實還是在SQL外處理好條件字符串再進行查詢和排序比較好.

對於MYSQL排序可能要改爲：

Select *

FROM table1

Where (ID IN (3,5,1,4,2))

ORDER BY FIND_IN_SET(ID, '3,5,1,4,2')