sql - Select data grouped by time over midnight -

i have table like:

id       timevalue -----    ------------- 1        06.07.15 06:43:01,000000000 2        06.07.15 12:17:01,000000000 3        06.07.15 18:21:01,000000000 4        06.07.15 23:56:01,000000000 5        07.07.15 04:11:01,000000000 6        07.07.15 10:47:01,000000000 7        07.07.15 12:32:01,000000000 8        07.07.15 14:47:01,000000000 

and want group data special times.
current query looks this:

select to_char(timevalue, 'yyyy\mm\dd'), count(id),    sum(case when to_char(timevalue, 'hh24mi') <=700 1 else 0 end) morning,   sum(case when to_char(timevalue, 'hh24mi') >700 , to_char(timevalue, 'hh24mi') <1400 1 else 0 end) daytime,   sum(case when to_char(timevalue, 'hh24mi') >=1400 1 else 0 end) evening table timevalue >= to_timestamp('05.07.2015','dd.mm.yyyy') group to_char(timevalue, 'yyyy\mm\dd') 

and getting output

day          overall     morning    daytime    evening  -----        --------- 2015\07\05   454         0          0          454 2015\07\06   599         113        250        236 2015\07\07   404         139        265        0 

so fine grouping on same day (0-7 o'clock, 7-14 o'clock , 14-24 o'clock)
question is: how can group on midnight?

for example count 6-14 , 14-23 , 23-6 o'clock on next day.

i hope understand question. welcome improve upper query if there better solution.

edit: tested now: sql fiddle

the key adjust group by before 6am gets grouped previous day. after that, counts pretty straight-forward.

select to_char(case when extract(hour timevalue) < 6                     timevalue - 1                     else timevalue                     end, 'yyyy\mm\dd') day,         count(*) overall,         sum(case when extract(hour timevalue) >= 6 , extract(hour timevalue) < 14                 1 else 0 end) morning,        sum(case when extract(hour timevalue) >= 14 , extract(hour timevalue) < 23                 1 else 0 end) daytime,        sum(case when extract(hour timevalue) < 6 or extract(hour timevalue) >= 23                 1 else 0 end) evening my_table timevalue >= to_timestamp('05.07.2015','dd.mm.yyyy') group to_char(case when extract(hour timevalue) < 6                     timevalue - 1                     else timevalue                     end, 'yyyy\mm\dd');