Aggregate function at Subquery And Performance Issue - sql

Question

I have query which i should select records from 1 table to insert another table once everyday(Select Into). It's big and enough complicated query for me because of i want to do it it 1 query. Here is piece of query which i want to change(it has many inner join and group by variables) :
Select RIGHT('0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN [EnteranceDevice] IN(1)
THEN CAST(EventDate as datetime) ELSE NULL END),(Select Cast([Start] as time)
as Start FROM [dbo].[Period] Where strDay=DATEPART(dw,CAST('2017-01-30' as date))
And Timezone=[dbo].[Timezone].Timezone))/60),2) +':'+
RIGHT('0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN [EnteranceDevice] IN(1)
THEN CAST(EventDate as datetime) ELSE NULL END),(Select Cast([Start] as time) as Start
FROM [dbo].[Period] Where strDay=DATEPART(dw,CAST('2017-01-30' as date))
And Timezone=[Timezone].Timezone))%60),2) AS WorkingHours from [dbo].[Events]
This query works and it give returns such answer 01:25 hours. When i want to change [EnteranceDevice] IN(1) to [EnteranceDevice] IN(Select ReaderInput from [SPS].[dbo].Users) it gives "Cannot perform an aggregate function on an expression containing an aggregate or a subquery" error
How can i solve this problem?
ReaderInput(nvarchar(50)) has such values(at 1 record) '1,3,5' because of it should store more than 1 device ID but EnteranceDevice is int. So Casting(Cast(EnteranceDevice as nvarchar(50)) IN(...) ) will work?
I'm sure that you see many performance issues at my code. I want to hear recommendations about query.

Answer 1

remember... saying something is "in" is the same same as saying left join and target is not null, so the refactoring is easy as follows:
could not read your code had to reformat it to have some sort of logic....
Select
RIGHT(
'0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN [EnteranceDevice] IN(1) THEN CAST(EventDate as datetime) ELSE NULL END),
(Select Cast([Start] as time) as Start FROM [dbo].[Period] Where strDay=DATEPART(dw,CAST('2017-01-30' as date)) And Timezone=[dbo].[Timezone].Timezone))/60),
2
) +
':'+
RIGHT(
'0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN [EnteranceDevice] IN(1) THEN CAST(EventDate as datetime) ELSE NULL END),
(Select Cast([Start] as time) as Start FROM [dbo].[Period] Where strDay=DATEPART(dw,CAST('2017-01-30' as date)) And Timezone=[Timezone].Timezone))%60),
2) AS WorkingHours
from [dbo].[Events]
First of all you have the same sub-query twice. Pull that out into a cross join
Select
RIGHT('0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN [EnteranceDevice] IN(1) THEN CAST(EventDate as datetime) ELSE NULL END),x.start)/60),2) +
':'+
RIGHT('0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN [EnteranceDevice] IN(1) THEN CAST(EventDate as datetime) ELSE NULL END),x.start)%60),2) AS WorkingHours
from [dbo].[Events]
cross join (
Select Cast([Start] as time) as Start
FROM [dbo].[Period]
Where strDay=DATEPART(dw,CAST('2017-01-30' as date))
And Timezone=[Timezone].Timezone
) x
Now join to users and check for null
Select
RIGHT('0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN u.ReaderInput is not null THEN CAST(EventDate as datetime) ELSE NULL END),x.start)/60),2) +
':'+
RIGHT('0'+LTRIM(DATEDIFF(MINUTE,MIN(CASE WHEN u.ReaderInput is not null THEN CAST(EventDate as datetime) ELSE NULL END),x.start)%60),2) AS WorkingHours
from [dbo].[Events]
left join [SPS].[dbo].Users u on [EnteranceDevice] = u.ReaderInput
cross join (
Select Cast([Start] as time) as Start
FROM [dbo].[Period]
Where strDay=DATEPART(dw,CAST('2017-01-30' as date))
And Timezone=[Timezone].Timezone
) x