Question

Hopefully someone can point me in the right direction here.

See below query.

SELECT day_id,month_id,time_id,
row_number() over (partition BY month_id order by day_id ) rn
FROM minute_bars_fact order by month_id, day_Id, time_id

Produces output:

DAY_ID      MONTH_ID    Time_id rn
02-JAN-11   JAN-2011    1080    1
02-JAN-11   JAN-2011    1081    2
02-JAN-11   JAN-2011    1082    3
02-JAN-11   JAN-2011    1083    4
02-JAN-11   JAN-2011    1084    5
02-JAN-11   JAN-2011    1085    6
02-JAN-11   JAN-2011    1086    7
02-JAN-11   JAN-2011    1087    8

My expectation here would be that rn would only be incrementing on each new day. Obviously that isn’t the case. Am i doing something wrong here?

Edit:

Day is not always the same.

02-JAN-11   JAN-2011    1436    357
02-JAN-11   JAN-2011    1437    358
02-JAN-11   JAN-2011    1438    359
02-JAN-11   JAN-2011    1439    360
03-JAN-11   JAN-2011    0   361
03-JAN-11   JAN-2011    1   362
03-JAN-11   JAN-2011    2   363
03-JAN-11   JAN-2011    3   364

Answer 1

My expectation here would be that rn would only be incrementing on each new day.

No this is incorrect. You would need to use RANK or DENSE_RANK to achieve this behaviour. Not ROW_NUMBER