ceilingdate

Ceilingdate is a date-time operation used in time series analysis and data processing. It rounds a given date or time up to the nearest boundary of a specified time unit, returning the smallest date-time that is greater than or equal to the input and lies on a boundary.

Units and behavior: The function takes a date-time value and a unit such as second, minute, hour, day, week, month, quarter, or year. If the input already lies on a boundary for that unit, ceilingdate returns the input unchanged; otherwise it advances to the next boundary. Boundaries depend on calendar rules and may be affected by time zone and locale. Weeks are defined by the chosen week start day, which varies by convention.

Examples: ceilingdate('2023-03-15 13:45', 'hour') -> '2023-03-15 14:00'. ceilingdate('2023-03-15', 'month') -> '2023-04-01'. ceilingdate('2023-03-15 00:00', 'day') -> '2023-03-15 00:00' since it is already at the start of the day. ceilingdate('2023-03-15', 'week') might yield the start of the next week depending on the week convention.

Implementation and naming: In various data libraries the same concept is implemented as ceiling_date, ceilingDate, or similar. It is the counterpart to floor_date, which rounds down to the previous boundary. This operation is common in resampling, binning, scheduling, and reporting tasks.