訂購在SQL

Question

一個nvarchar場我使用下面的查詢的SQL命令字段

Select Distinct x From t where c=1 order by x asc 

X是一個nvarchar列，但目前列有以下值

無論如何訂購的價值是這樣的：

沒有獎，1,2,3,4,5,6,7,8,9,10

Answer 1

在SQL Server 2012+可以使用try_cast，但你將不得不改變distinct爲group by：

SELECT x 
FROM t 
WHERE c=1 
GROUP BY x 
ORDER BY Try_Cast(x as int) 

對於老版本，你可以使用union：

SELECT x 
FROM 
(
    SELECT x, CAST(x as int) as sort 
    FROM t 
    WHERE c = 1 
    AND ISNUMERIC(x) = 1 

    UNION 

    SELECT x, NULL 
    FROM t 
    WHERE c = 1 
    AND ISNUMERIC(x) = 0 
) as distinctX 
ORDER BY sort