CEIL, FLOOR, and ROUND for datetime data types

with vals as (
  select
    interval '+123-5' year(9) to month ymi,
    interval '+0 12:34:56' day to second dsi,
    to_date ( '12-APR-2023 12:34:56', 'DD-MON-YYYY HH24:MI:SS' ) dt,
    to_timestamp ( '12-APR-2023 12:34:56', 'DD-MON-YYYY HH24:MI:SS' ) ts
)
select
  -- CEIL rounds up values
  ceil ( ymi ) as year_ceil,
  ceil ( dsi ) as day_ceil,
  ceil ( dt ) as dt_day_ceil,
  ceil ( ts ) as ts_day_ceil,
  -- FLOOR rounds down the datetime value to the units in the second paramter
  floor ( ymi, 'year' ) as ymi_year_floor,
  floor ( dsi, 'hh24' ) as dsi_hour_floor,
  floor ( dt, 'hh24' ) as dt_hour_floor,
  floor ( ts, 'hh24' ) as ts_hour_floor,
  -- ROUND now supports INTERVALs
  round ( dsi, 'mi' ) as dsi_minute_round
from   vals;

SQL> with vals as (
  2    select
  3      interval '+123-5' year(9) to month ymi,
  4      interval '+0 12:34:56' day to second dsi,
  5      to_date ( '12-APR-2023 12:34:56', 'DD-MON-YYYY HH24:MI:SS' ) dt,
  6      to_timestamp ( '12-APR-2023 12:34:56', 'DD-MON-YYYY HH24:MI:SS' ) ts
  7  )
  8  select
  9    -- CEIL rounds up values
 10    ceil ( ymi ) as year_ceil,
 11    ceil ( dsi ) as day_ceil,
 12    ceil ( dt ) as dt_day_ceil,
 13    ceil ( ts ) as ts_day_ceil,
 14    -- FLOOR rounds down the datetime value to the units in the second paramter
 15    floor ( ymi, 'year' ) as ymi_year_floor,
 16    floor ( dsi, 'hh24' ) as dsi_hour_floor,
 17    floor ( dt, 'hh24' ) as dt_hour_floor,
 18    floor ( ts, 'hh24' ) as ts_hour_floor,
 19    -- ROUND now supports INTERVALs
 20    round ( dsi, 'mi' ) as dsi_minute_round
 21  from   vals;

YEAR_CE DAY_CEIL            DT_DAY_CEIL       TS_DAY_CEIL       YMI_YEA DSI_HOUR_FLOOR      DT_HOUR_FLOOR     TS_HOUR_FLOOR     DSI_MINUTE_ROUND
------- ------------------- ----------------- ----------------- ------- ------------------- ----------------- ----------------- -------------------
+124-00 +01 00:00:00.000000 13-APR-2023 00:00 13-APR-2023 00:00 +123-00 +00 12:00:00.000000 12-APR-2023 12:00 12-APR-2023 12:00 +00 12:35:00.000000