How do I change the format of nvarchar to datetime?

My code generates some dataset in a 10 minute log or a 30 minute log, but the DateTime format is '1900-01-01 14:20:00'

. I need '2009-05-13 14:20:00'

, so I want to change it.

See table 1 and table 2 below.

declare @date1 nvarchar(100) , @date2 nvarchar(100) , @countgap int,@count int 
set @date1='2009-05-12'
set @date2 = '2009-05-13'
set @countgap = 10 --per ten minutes


CREATE TABLE #Temp (VisitingCount int, [Time] int, [Date] datetime )
DECLARE @DateNow DATETIME,@i int,@Time int, @Date datetime
set @DateNow='00:00'  
set @i=1;  
insert into #Temp(VisitingCount,[Time],[Date]) values(0,0,@DateNow )
while(@i<(24*60)/@countgap)  
    begin  
        set @DateNow = DATEADD(minute, @countgap, @DateNow)
        set @Time = (datepart(hour,@DateNow)*60+datepart(minute,@DateNow))/@countgap 
        set @Date = CONVERT(VARCHAR(5),@DateNow, 108)
        insert into #Temp(VisitingCount,[Time],[Date]) values(0,@Time,@Date )
        set @i=@i+1
    end

select 
Sum(VisitingCount) as VisitingCount, [Time], 
Cast( RIGHT('00'+Cast([Time]*@countgap/60 as varchar(2)  ),2) +':'+RIGHT('00'+Cast( [Time]*@countgap%60 as varchar(2)  ),2)  as Smalldatetime)as VisitingGap
from (
  select 0 as VisitingCount, [Time] from #Temp
  Union All
    select count(page) as VisitingCount, 
    (datepart(hour,Date)*60+datepart(minute,Date))/@countgap as [Time] 
    from scr_SecuristLog
    where Date between @date1 and @date2
    GROUP BY (datepart(hour,Date)*60+datepart(minute,Date))/@countgap
  ) X
group by [Time]
order by  2 asc 

      

        
        
        
      

    

Table 1

VCount Time VisitingGap
 6 86 1900-01-01 14:20:00
17 87 1900-01-01 14:30:00
 9 88 1900-01-01 14:40:00
20 89 1900-01-01 14:50:00
19 90 1900-01-01 15:00:00
 0 91 1900-01-01 15:10:00
 7 92 1900-01-01 15:20:00
 4 93 1900-01-01 15:30:00
 8 94 1900-01-01 15:40:00
 9 95 1900-01-01 15:50:00
 0 96 1900-01-01 16:00:00
20 97 1900-01-01 16:10:00
24 98 1900-01-01 16:20:00

Table2

VCount Time VisitingGap
...
 6 86 2009-05-13 14:20:00
17 87 2009-05-13 14:30:00
 9 88 2009-05-13 14:40:00
20 89 2009-05-13 14:50:00
19 90 2009-05-13 15:00:00
...

I think I need to change this:

Cast( RIGHT('00'+Cast([Time]*@countgap/60 as varchar(2)  ),2) +':'+RIGHT('00'+Cast( [Time]*@countgap%60 as varchar(2)  ),2)  as Smalldatetime)as VisitingGap