Oracle - Counts by time intervals - oracle

Question

I have a table with some entries, and a DATE column indicating the date/time the record was inserted. What I need is to create a query where the data will be displayed in a tabular format with counts at the 15 minute intervals for the entire day. So, the output would look like:
LABEL DAY DATE 00:00 00:15 00:30 00:45.........23:30 23:45
ORDERS MONDAY 4/19/2021 1 1 0 1 0 1
ORDERS TUESDAY 4/20/2021 1 0 0 0 1 0
This is what they are asking for......and probably have to put that into a CSV at some later date. But for now, is there any simple way to make a query like this, or are we talking writing a procedure?

Answer 1

You can use conditional aggregation:
SELECT label,
TO_CHAR(TRUNC("DATE"), 'DAY') AS day,
TRUNC("DATE") AS "DATE",
COUNT( CASE TRUNC(("DATE" - TRUNC("DATE"))*96) WHEN 0 THEN 1 END ) AS "00:00",
COUNT( CASE TRUNC(("DATE" - TRUNC("DATE"))*96) WHEN 1 THEN 1 END ) AS "00:15",
COUNT( CASE TRUNC(("DATE" - TRUNC("DATE"))*96) WHEN 2 THEN 1 END ) AS "00:30",
COUNT( CASE TRUNC(("DATE" - TRUNC("DATE"))*96) WHEN 3 THEN 1 END ) AS "00:45",
COUNT( CASE TRUNC(("DATE" - TRUNC("DATE"))*96) WHEN 4 THEN 1 END ) AS "01:00"
-- ...
FROM table_name
GROUP BY TRUNC( "DATE" ), label
ORDER BY TRUNC( "DATE" ), label
Or PIVOT:
SELECT TO_CHAR(dt,'FMDAY') AS day,
t.*
FROM (
SELECT label,
TRUNC("DATE") AS dt,
TRUNC( ("DATE" - TRUNC("DATE")) * 96 ) AS time
FROM table_name
)
PIVOT(
COUNT(*) FOR time IN (
0 AS "00:00",
1 AS "00:15",
2 AS "00:30",
3 AS "00:45",
4 AS "01:00",
5 AS "01:15",
-- ...
92 AS "23:00",
93 AS "23:15",
94 AS "23:30",
95 AS "23:45"
)
) t;
db<>fiddle here

Answer 2

I'll try to describe as detailed as I can.
First of all you can truncate your minutes to 15 minutes intervals:
--test data:
with t(label,dt) as (
select 'ORDERS',date'2021-04-21'+numtodsinterval(level*2,'minute')
from dual
connect by level<=30
)
--main query:
select
dt, label, weekday, hh24, quarter, quarter*15 rounded_minutes
from
(
select
dt
,label
,to_char(dt,'day') weekday
,to_char(dt,'hh24') hh24
,trunc(to_number(to_char(dt,'mi'))*4/60) quarter
from t
);
Results:
DT LABEL WEEKDAY HH24 QUARTER ROUNDED_MINUTES
------------------- ------ ---------- ---- ---------- ---------------
2021-04-21 00:02:00 ORDERS wednesday 00 0 0
2021-04-21 00:04:00 ORDERS wednesday 00 0 0
2021-04-21 00:06:00 ORDERS wednesday 00 0 0
2021-04-21 00:08:00 ORDERS wednesday 00 0 0
2021-04-21 00:10:00 ORDERS wednesday 00 0 0
2021-04-21 00:12:00 ORDERS wednesday 00 0 0
2021-04-21 00:14:00 ORDERS wednesday 00 0 0
2021-04-21 00:16:00 ORDERS wednesday 00 1 15
2021-04-21 00:18:00 ORDERS wednesday 00 1 15
2021-04-21 00:20:00 ORDERS wednesday 00 1 15
2021-04-21 00:22:00 ORDERS wednesday 00 1 15
2021-04-21 00:24:00 ORDERS wednesday 00 1 15
2021-04-21 00:26:00 ORDERS wednesday 00 1 15
2021-04-21 00:28:00 ORDERS wednesday 00 1 15
2021-04-21 00:30:00 ORDERS wednesday 00 2 30
2021-04-21 00:32:00 ORDERS wednesday 00 2 30
2021-04-21 00:34:00 ORDERS wednesday 00 2 30
2021-04-21 00:36:00 ORDERS wednesday 00 2 30
2021-04-21 00:38:00 ORDERS wednesday 00 2 30
2021-04-21 00:40:00 ORDERS wednesday 00 2 30
2021-04-21 00:42:00 ORDERS wednesday 00 2 30
2021-04-21 00:44:00 ORDERS wednesday 00 2 30
2021-04-21 00:46:00 ORDERS wednesday 00 3 45
2021-04-21 00:48:00 ORDERS wednesday 00 3 45
2021-04-21 00:50:00 ORDERS wednesday 00 3 45
2021-04-21 00:52:00 ORDERS wednesday 00 3 45
2021-04-21 00:54:00 ORDERS wednesday 00 3 45
2021-04-21 00:56:00 ORDERS wednesday 00 3 45
2021-04-21 00:58:00 ORDERS wednesday 00 3 45
2021-04-21 01:00:00 ORDERS wednesday 01 0 0
As you can see we calculate a quarter of hour using simple trunc(to_number(to_char(dt,'mi'))*4/60). So we just need to multiply it to 4 to get rounded minutes.
Then you can just concatenate them and use pivot clause to aggregate:
with t(label,dt) as (
select 'ORDERS',date'2021-04-21'+numtodsinterval(level*2,'minute')
from dual
connect by level<=3000
)
select *
from (
select
label, weekday, hh24||':'||to_char(quarter*15,'fm00') hhmi
from
(
select
dt
,label
,to_char(dt,'day') weekday
,to_char(dt,'hh24') hh24
,trunc(to_number(to_char(dt,'mi'))*4/60) quarter
from t
)
)
pivot(
count(*) for hhmi in (
'00:00','00:15','00:30','00:45','01:00','01:15','01:30','01:45'
,'02:00','02:15','02:30','02:45','03:00','03:15','03:30','03:45'
,'04:00','04:15','04:30','04:45','05:00','05:15','05:30','05:45'
,'06:00','06:15','06:30','06:45','07:00','07:15','07:30','07:45'
,'08:00','08:15','08:30','08:45','09:00','09:15','09:30','09:45'
,'10:00','10:15','10:30','10:45','11:00','11:15','11:30','11:45'
,'12:00','12:15','12:30','12:45','13:00','13:15','13:30','13:45'
,'14:00','14:15','14:30','14:45','15:00','15:15','15:30','15:45'
,'16:00','16:15','16:30','16:45','17:00','17:15','17:30','17:45'
,'18:00','18:15','18:30','18:45','19:00','19:15','19:30','19:45'
,'20:00','20:15','20:30','20:45','21:00','21:15','21:30','21:45'
,'22:00','22:15','22:30','22:45','23:00','23:15','23:30','23:45'
)
);
Results (shortened for readbility):
LABEL WEEKDAY '00:00' '00:15' '00:30' '00:45' '01:00' '01:15' ... '23:15' '23:30' '23:45'
------ ---------- ---------- ---------- ---------- ---------- ---------- ---------- ... ---------- ---------- ----------
ORDERS friday 8 7 8 7 8 7 ... 7 8 7
ORDERS saturday 8 7 8 7 8 7 ... 7 8 7
ORDERS sunday 8 7 8 7 8 7 ... 0 0 0
ORDERS thursday 8 7 8 7 8 7 ... 7 8 7
ORDERS wednesday 7 7 8 7 8 7 ... 7 8 7