在SQL中修剪输出

Question

I have this query

 Select distinct 
    tag 
 from 
     (SELECT  *
      FROM [piarchive].[picomp2]
      WHERE tag like '%CPU_Active' 
        and time between '2014/10/01 10:13:08' and '2014/10/01 10:18:37'
        and value = -524289 
      order by time desc) as t1

With this I am getting output

RSV23.VMS_CPU01_1_0.CPU_Active

I need to trim this output to

RSV23.VMS_CPU1_1_0

And need to use this trim output in different query like below

 SELECT  *
 FROM [piarchive].[picomp2]
 WHERE tag like 'RSV23.VMS_CPU01_1_0%' and tag not like '%CPU_Active' and  time   
 between '2014/10/01 10:13:08'and'2014/10/01 10:18:37'  order by time desc

How can I trim first out and use that output in second query?

Answer 1

I just got the answer.

 SELECT top 6 *
 FROM [piarchive].[picomp2]
 WHERE tag like 
 (
   Select distinct left(tag,19) + '%' 
   from (SELECT  *
   FROM [piarchive].[picomp2]
   WHERE tag like '%CPU_Active' and  time between '2014/10/01 10:13:08'and'2014/10/01 10:18:37'
   and value=-524289 order by time desc) as t1
 )  
   and tag not like '%CPU_Active' and tag not like '%Program%' and time between '2014/10/01  
   10:13:08'and'2014/10/01 10:18:37'  order by time desc

Answer 2

You should find last index of dot (.) in query result and chop the string after that index.

declare @result nvarchar(100)
set @result = (Select distinct tag from (SELECT  * FROM [piarchive].[picomp2] WHERE tag like '%CPU_Active' and time between '2014/10/01 10:13:08' and '2014/10/01 10:18:37' and value = -524289 order by time desc) as t1)

declare @LastIndex int 
set @LastIndex = len(@result) - charindex('.', reverse(@result))

substring(@result,0,@LastIndex) // this will give you the required result