How to Compare day and night based on current time

Question

Hi,
Day starts 08:00 -18:00(start time-end time)
Night starts 18:00-08:00(st-et)
for day it's easy I compare current time between st and et in logs table.
for night if I use the same the process it falls after midnight coz current time is not in between st and et. 
Example : 00:00 between 18:00 and 08:00.
To over come above I stared comparing with datetime.
for day it's fine.
for night , it inserts one log at 18:00 and updates till 23:59, after 00:00 it's not updating and adds new record then problem starts.
can anyone give me some idea how to handle this please?
Cheers :)

Answer 1

create table #t (st time, et time)
insert into #t values ('08:00','18:00')
insert into #t values ('18:00','08:00')
declare @time time='00:00';
select st, et from #t
where case when @time='00:00' then '23:59'
else @time end >st and et< st
or @time between st and et
Best Regards,Uri Dimant SQL Server MVP,
http://sqlblog.com/blogs/uri_dimant/
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