请看看以下SQL,不知作何解释?

Question

select 
    Result=case when (  select convert(varchar(1000),  isnull(PathScript,'1=2'
                                                              )
                                      )
                        from RE_Path 
                        where FlowCode = @AuthID
                     )  
       then 1 
                else 0
           end
from  Table1
重排一下版面，这样看得比较清楚了。我看好象有语法错误。

Answer 1

猜的:如果有记录就是1, 改一下就是:
select Result=(case when exists(select convert(varchar(1000),  isnull(PathScript,'1=2')) from RE_Path 
                                         where FlowCode = @AuthID)  
 then 1 else 0 end)
from  Table1

Answer 2

谢谢楼上的两位先! 
To zheninchangjiang(john shu)：  convert(varchar(1000),  isnull(PathScript,'1=2'))   不是没任何意义吗?

Answer 3

我想明白了!
select 
    Result=case when (  select convert(varchar(1000),  isnull(PathScript,'1=2'
                                                              )
                                      )
                        from RE_Path 
                        where FlowCode = @AuthID
                     )  
       then 1 
                else 0
           end
from  Table1
其中:
"select convert(varchar(1000),  isnull(PathScript,'1=2'
                                                              )
                                      )
                        from RE_Path 
                        where FlowCode = @AuthID"
会得到一个表达式，如col1=col2 ,而Table1 中有列col1,col2, 
所以是比较table1中col1,col2是否相等!再次谢谢两位仁兄！