T-SQL - 如何处理SELECT如果错误逻辑

Question

我在下面有一个简单的选择声明：

SELECT Code =   Cast([Code] as int)
FROM dbo.table 

我收到错误：

  

转换nvarchar值时转换失败＆＃39;？＆＃39>到数据类型   中间体

我想编写IFERROR或CASE语句，用一个数字替换错误，例如-9999

Answer 1

SELECT 
    Code = CASE 
               WHEN ISNUMERIC(Code) = 1 THEN Cast([Code] as int) 
               ELSE -9999 
    END
FROM 
    dbo.table

Answer 2

SELECT Code = Cast((case when [Code] = '?' then -9999 else [Code] end) as int)
FROM dbo.table