--> 测试数据: @T
declare @T table (col varchar(10))
insert into @T
select 12345678 union all
select 18760216

--预设信息1
declare @s1 varchar(20) set @s1='转成失败'

--预设信息2
declare @s2 varchar(20) set @s2='转成成功'

--查询
select 
case when isdate(col)=1 
     then convert(varchar(10),cast(col as datetime),120)
     else col end as col,
case when isdate(col)=1 
     then @s2 else @s1 end as MessageInfo
from @T
/*
col        MessageInfo
---------- --------------------
12345678   转成失败
1876-02-16 转成成功
*/

------解决方案--------------------
探讨


引用:

SQL code

--> 测试数据: @T
declare @T table (col varchar(10))
insert into @T
select 12345678 union all
select 18760216

--预设信息1
declare @s1 varchar(20) set @s1='转成失败'

--预设信息2
……