Interval 

The family of data types representing time and date intervals. The resulting types of the INTERVAL operator.

Structure:

  • Time interval as an unsigned integer value.
  • Type of an interval.

Supported interval types:

  • SECOND
  • MINUTE
  • HOUR
  • DAY
  • WEEK
  • MONTH
  • QUARTER
  • YEAR

For each interval type, there is a separate data type. For example, the DAY interval corresponds to the IntervalDay data type:

SELECT toTypeName(INTERVAL 4 DAY)
┌─toTypeName(toIntervalDay(4))─┐
│ IntervalDay                  │
└──────────────────────────────┘

Usage Remarks 

You can use Interval-type values in arithmetical operations with Date and DateTime-type values. For example, you can add 4 days to the current time:

SELECT now() as current_date_time, current_date_time + INTERVAL 4 DAY
┌───current_date_time─┬─plus(now(), toIntervalDay(4))─┐
│ 2019-10-23 10:58:45 │           2019-10-27 10:58:45 │
└─────────────────────┴───────────────────────────────┘

Intervals with different types can’t be combined. You can’t use intervals like 4 DAY 1 HOUR. Specify intervals in units that are smaller or equal to the smallest unit of the interval, for example, the interval 1 day and an hour interval can be expressed as 25 HOUR or 90000 SECOND.

You can’t perform arithmetical operations with Interval-type values, but you can add intervals of different types consequently to values in Date or DateTime data types. For example:

SELECT now() AS current_date_time, current_date_time + INTERVAL 4 DAY + INTERVAL 3 HOUR
┌───current_date_time─┬─plus(plus(now(), toIntervalDay(4)), toIntervalHour(3))─┐
│ 2019-10-23 11:16:28 │                                    2019-10-27 14:16:28 │
└─────────────────────┴────────────────────────────────────────────────────────┘

The following query causes an exception:

select now() AS current_date_time, current_date_time + (INTERVAL 4 DAY + INTERVAL 3 HOUR)
Received exception from server (version 19.14.1):
Code: 43. DB::Exception: Received from localhost:9000. DB::Exception: Wrong argument types for function plus: if one argument is Interval, then another must be Date or DateTime..

See Also 

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