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:
NANOSECOND
MICROSECOND
MILLISECOND
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
- INTERVAL operator
- toInterval type conversion functions