SQL server列 截取字符串

要是BIZNAME有两个括号就不行了
select substring(bizname,charindex('(',bizname),charindex(')',bizname))
from 表名
where charindex('(',bizname)>0

charindex('(',bizname)>0 这个条件是bizname 栏位裏面必须有()

declare @a varchar(50)
select @a= ziduan from table12
declare @i int ,@j int
set @i = Charindex('(',@a)
set @j = Charindex(')',@a)
declare @e varchar(20)
set @e=substring(@a,@i+1,@j-2)
print @e

select substring(charindex('(',BizName)+1,charindex')',BizName)-1)
from 表名 where charindex('(',BizName)>1