SSRS Report very slow after doing inner join in sql query

Question

First I used a query without the second select statement, the positive was that the report was really fast if I choose a long time period, but it displayed me every weekends and holidays. That was not a big issue, then I excluded every free days with the filter option in SSRS, after this the report showed me only the workdays, but the problem was, there were additional rows with a 0 and this affected the calculations.

The only solution was to add a second select statement "Scheduled". After I added an inner join the report runs very slow. The second Select Statement is a schedule and it excludes all the weekends and holidays, and this does not display any extra row if I run it. But the big Problem is, that the report runs really slow. And If I choose over a period of six month it displays me a "Timeout Error".
The query:

SELECT c.date, 
       c.team, 
       c.NAME, 
       c.prod, 
       c.product 
FROM   (SELECT intervaldate AS Date, 
               tsystem.NAME AS NAME, 
               productname  AS Product, 
               teamname     AS Team, 
               Sum(CASE 
                     WHEN countername = 'Prod' THEN displayunits 
                     ELSE 0 
                   END)     AS Prod 
        FROM   count 
               INNER JOIN tsystem 
                       ON count.systemid = tsystem.id 
        WHERE  intervaldate >= @StartDateTime 
               AND intervaldate <= @EndDateTime 
               AND tsystem.id IN (SELECT systemid 
                                  FROM   viewsystem 
                                  WHERE  viewid = 122) 
        GROUP  BY intervaldate, 
                  teamname, 
                  tsystem.NAME, 
                  productname) c 
       INNER JOIN (SELECT sh.scheduled AS Scheduled, 
                          sc.NAME      AS NAME 
                   FROM   history sh 
                          INNER JOIN schedule sc 
                                  ON ( sc.id = sh.scheduleid ) 
                   WHERE  scheduled != 0) p 
               ON p.NAME = c.NAME 

Is there any possibility to make it faster?

Answer 1

You need to replace below part of query (sub query) with join

-> and tsystem.ID in (Select SystemID from ViewSystem where ViewID = 122)

-> Inner JOIN ViewSystem on tsystem.ID=ViewSystem.SystemID where ViewID=122

Joins are way more faster than sub queries.