docs-v2/content/shared/influxql-v3-reference/functions/date-time.md

Use InfluxQL date and time functions to perform time-related operations.

• now()
• time()
• tz()

now()

Returns the current system time (UTC). Supported only in the WHERE clause.

now()

time()

Used in the GROUP BY clause to group data into time-based intervals, also known as "windows", using the specified interval. Timestamps in the time column are updated to the start boundary of the window they're in and grouped by time. Windows use preset round-number boundaries based on the specified interval that are independent of time conditions in the WHERE clause.

This operation can be used to do the following:

• Downsample data by aggregating multiple points in each window into a single point per window.
• Normalize irregular time series data to occur at regular intervals.

Supported only in the GROUP BY clause.

time(interval[, offset])

Arguments

• interval: Duration literal that specifies the window interval.
• offset: Duration literal that shifts preset time boundaries forward or backward. Can be positive or negative. Default is 0s.

Examples

{{< expand-wrapper >}}

{{% expand "Downsample data into time-based intervals" %}}

The following example uses the Bitcoin price sample dataset.

SELECT
  MEAN(price)
FROM bitcoin
WHERE
  code = 'GBP'
  AND time >= '2023-05-01T00:00:00Z'
  AND time < '2023-05-15T00:00:00Z'
GROUP BY time(2d)

{{% influxql/table-meta %}} name: bitcoin {{% /influxql/table-meta %}}

time	mean
2023-05-01T00:00:00Z	23680.120447159094
2023-05-03T00:00:00Z	24048.71484033149
2023-05-05T00:00:00Z	24461.9194901099
2023-05-07T00:00:00Z	23796.43801933702
2023-05-09T00:00:00Z	23118.709889285707
2023-05-11T00:00:00Z	22465.008364444446
2023-05-13T00:00:00Z	22499.464763186803

{{% /expand %}} {{< /expand-wrapper >}}

tz()

Applies a timezone offset to timestamps in query results. Offsets include any seasonal offset such as Daylight Savings Time (DST) or British Summer Time (BST). Supported only in the time zone clause.

tz(time_zone)

Arguments

• time_zone: Timezone string literal to adjust times to. Uses timezone names defined in the Internet Assigned Numbers Authority time zone database.

Examples

{{< expand-wrapper >}}

{{% expand "Return the UTC offset for Chicago's time zone" %}}

The following example uses the Home sensor sample dataset.

{{% influxdb/custom-timestamps %}}

SELECT *
FROM home
WHERE
  room = 'Kitchen'
  AND time >= '2022-01-01T08:00:00Z'
  AND time <= '2022-01-01T12:00:00Z'
tz('America/Chicago')

{{% influxql/table-meta %}} name: home {{% /influxql/table-meta %}}

time	co	hum	room	temp
2022-01-01T02:00:00-06:00	0	35.9	Kitchen	21
2022-01-01T03:00:00-06:00	0	36.2	Kitchen	23
2022-01-01T04:00:00-06:00	0	36.1	Kitchen	22.7
2022-01-01T05:00:00-06:00	0	36	Kitchen	22.4
2022-01-01T06:00:00-06:00	0	36	Kitchen	22.5

{{% /influxdb/custom-timestamps %}} {{% /expand %}} {{< /expand-wrapper >}}