次のようなものを試してください(ここでは sqlfiddle です):
select case
when time >= 23 then '23 =< TIME'
when time < 23 and time >= 22.3 then '23 > TIME >= 22,3'
when time < 22.3 and time >= 21.6 then '22,3 > TIME >= 21,6'
when time < 21.6 and time >= 20.9 then '21,6 > TIME >= 20,9'
else '20,9 > TIME'
end || ' with value '|| count(*) v
from your_table
group by case
when time >= 23 then '23 =< TIME'
when time < 23 and time >= 22.3 then '23 > TIME >= 22,3'
when time < 22.3 and time >= 21.6 then '22,3 > TIME >= 21,6'
when time < 21.6 and time >= 20.9 then '21,6 > TIME >= 20,9'
else '20,9 > TIME'
end
そして結果:
21,6 > TIME >= 20,9 with value 8
20,9 > TIME with value 4
22,3 > TIME >= 21,6 with value 6
23 > TIME >= 22,3 with value 15
23 =< TIME with value 66
更新: DavidAldrige が提案したように、サブクエリを使用できます。
select intrvl || ' with value '|| count(*) v
from
(select case
when time >= 23 then '23 =< TIME'
when time < 23 and time >= 22.3 then '23 > TIME >= 22,3'
when time < 22.3 and time >= 21.6 then '22,3 > TIME >= 21,6'
when time < 21.6 and time >= 20.9 then '21,6 > TIME >= 20,9'
else '20,9 > TIME'
end intrvl, time
from t)
group by intrvl
そして、ここに別のデモがあります