使用UNPIVOT：

  SELECT  MAX（vx） FROM  MyTable  AS  a 
 UNPIVOT（vx  FOR 值 IN （Col1，Col2，Col3，Col4））  AS  up 

错误：错过了AS a[ / edit]

Solution1 by OriginalGriff [ ^ ]非常好。作为替代方案，请检查：

  SELECT  MAX（A. MyValue）
 FROM （
 SELECT  Col1  AS  MyValue 
 FROM  TableName 
 UNION   ALL  
 SELECT  Col2  AS  MyValue 
 FROM  TableName 
 UNION   ALL  
 SELECT  Col3  AS  MyValue 
 FROM  TableName 
 UNION   ALL  
 SELECT  Col4  AS  MyValue 
 FROM  TableName 
） AS  A 

Hi,

Please find the below sql server - total table.

Col 1 Col 2 Col 3 Col 4
1 5 6 8
11 14 18 12


i want to out put of maximum number in the total table.

Use UNPIVOT:

SELECT MAX(vx) FROM MyTable AS a
UNPIVOT (vx FOR Value IN (Col1, Col2, Col3, Col4)) AS up

[edit]Typo: missed "AS a"[/edit]

Solution1 by OriginalGriff[^] is very good. As an alternative, check this:

SELECT MAX(A.MyValue)
FROM (
    SELECT Col1 AS MyValue
    FROM TableName 
    UNION ALL
    SELECT Col2 AS MyValue
    FROM TableName 
    UNION ALL
    SELECT Col3 AS MyValue
    FROM TableName 
    UNION ALL
    SELECT Col4 AS MyValue
    FROM TableName 
) AS A