ClickHouse/docs/en/data_types/special_data_types/interval.md

Interval

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

!!! warning "Warning" You can't use the Interval data types for storing values in tables.

Structure:

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

Supported interval types:

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

For each interval type, there is the separated data type. For example, the DAY interval is expressed as 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 of different types can't be combined. You can't use intervals like 4 DAY 1 HOUR, express intervals in the units that smaller or equal the the smallest unit of the interval. For example, 1 day and an hour interval can be expressed as 25 HOUR or 90000 SECOND.

You can't perform arithmetical operations with the Interval-type values, but you can add intervals of different types consequently to some value. 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 the 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 convertion functions