Get specific time threshold in SQL - sql

Question

I have a console app that will choose records based on if the user has chosen to be notified daily at a specific hour of the day as well as all records where the user has chosen hourly.
The job will run every 15 minutes.
How do I find a threshold of time between 5 minutes before and 5 minutes after the top of the hour?
This is my code
Declare #Now datetime
Declare #NowHour int
Declare #NowMinute int
Declare #NewNow nvarchar(50)
Set #Now = {fn Now()}
Set #NowHour = (SELECT DATENAME(hh, #Now))
Set #NowMinute = (SELECT DATENAME(mi, #Now))
Set #NewNow = Cast(Cast(#NowHour As nvarchar(2)) + ':' + Cast(#NowMinute As nvarchar(2)) as Time)
Select #Now, #NowHour, #NowMinute, #NewNow
Select * From vw_consumerAlerts
Where casexid not in
(Select casexid from alerthistory)
And Name = 'Always'
Or ([Hour] Between DateAdd(minute, -5, #NewNow) And DateAdd(minute, -5, #NewNow))
This is the error I'm getting
The data types time and datetime are incompatible in the greater than or equal to operator.
I got it, I had [Hour] and #NewNow swapped, now I get the correct results with:
(#NewNow Between DateAdd(minute, -5, [Hour]) And DateAdd(minute, 5, [Hour]))

Answer 1

Assuming you have defined #TheHour as being the hour in question with 00 minutes/seconds:
WHERE mydatecol BETWEEN DATEADD(minute, -5, #TheHour) AND DATEADD(minute, 5, #TheHour)
UPDATE
See this:
select 1
where cast('1/1/2010 1:04pm' as time)
between cast('1/1/2010 12:55pm' AS time)
and cast ('1/1/2010 1:05pm' as time)
time and datetime are different, so you need to cast your datetime to time as I've done in the crude example here.
So in your case:
Select * From vw_consumerAlerts
Where casexid not in
(Select casexid from alerthistory)
And Name = 'Always'
Or ([Hour] Between cast(DateAdd(minute, -5, #NewNow) as time)
And cast(DateAdd(minute, -5, #NewNow) as time))