我不太清楚你所说的“智能”guid到底是什么意思，但是为什么不直接将它转换成一个char并按位置拉出部分呢？

create table t(myguid uniqueidentifier);
declare @p tinyint = 5;    
select      case @p
               when 1 then left(c.v, 8)
               when 2 then substring(c.v, 10, 4)
               when 3 then substring(c.v, 15, 4)
               when 4 then substring(c.v, 20, 4)
               when 5 then right(c.v, 12)
            end
from        t 
cross apply (select cast(t.myguid as char(36))) c(v)

你可以使用openjson

DECLARE @Guid UNIQUEIDENTIFIER = 'A7DDAA60-C33A-4D7A-A2D8-ABF20127C9AE', 
@s varchar(100)

Select @s = replace(@guid,'-','","')

Select * from
(
    Select [key] + 1 as Poistion, Value as Part
    FROM OPENJSON('["' +  @s + '"]')
) Q
Where Poistion in (2,4)

这是小提琴。