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How to combine these two SQL statements?

I have 2 SQL queries. They get counts based the variable equals either CMSUID or CASUID value in the table. Otherwise, they are exactly the same. How can I combine them into a single query, perhaps using a CASE statement.

select @cntCM_CNF = count(distinct(c.ID_Case))
from dbo.Cases c
join dbo.vew_CasePersonnelSystemIDs vcps on c.ID_Case = vcps.ID_Case
join hearings h on c.ID_Case = h.ID_Case
where vcps.CMSUID = @nSUID
    and h.HearingDate > getdate()
    and h.OnCalendar = 1 and h.Scheduled = 1
    and dbo.fn_HearingConfirmedNoHOs(h.ID_Hearing) < 2

select @cntCC_CNF = count(distinct(c.ID_Case))
from dbo.Cases c
join dbo.vew_CasePersonnelSystemIDs vcps on c.ID_Case = vcps.ID_Case
join hearings h on c.ID_Case = h.ID_Case
where vcps.CASUID = @nSUID
    and h.HearingDate > getdate()
    and h.OnCalendar = 1 and h.Scheduled = 1
    and dbo.fn_HearingConfirmedNoHOs(h.ID_Hearing) < 2  

I can’t figure out how to combine them because the result is a count of distinct items. Not sure how to make that happen.

Answer 1

is it…

select 
    @cntCM_CNF = count(distinct case when vcps.CMSUID = @nSUID then c.ID_Case else null end),
    @cntCC_CNF = count(distinct case when vcps.CASUID = @nSUID then c.ID_Case else null end)
from dbo.Cases c
join dbo.vew_CasePersonnelSystemIDs vcps on c.ID_Case = vcps.ID_Case
join hearings h on c.ID_Case = h.ID_Case
where 
    h.HearingDate > getdate()
    and h.OnCalendar = 1 and h.Scheduled = 1
    and dbo.fn_HearingConfirmedNoHOs(h.ID_Hearing) < 2 AND
    (vcps.CASUID = @nSUID OR vcps.CMSUID = @nSUID) --<<<<added for performance reasons