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Manipulate timestamps with Flux Manipulate timestamps Use Flux to process and manipulate timestamps.
enterprise_influxdb_v1
name parent
Manipulate timestamps Query with Flux
20 /influxdb/v2/query-data/flux/manipulate-timestamps/

Every point stored in InfluxDB has an associated timestamp. Use Flux to process and manipulate timestamps to suit your needs.

{{% note %}} If you're just getting started with Flux queries, check out the following:

Convert timestamp format

Unix nanosecond to RFC3339

Use the time() function to convert a Unix nanosecond timestamp to an RFC3339 timestamp.

time(v: 1568808000000000000)
// Returns 2019-09-18T12:00:00.000000000Z

RFC3339 to Unix nanosecond

Use the uint() function to convert an RFC3339 timestamp to a Unix nanosecond timestamp.

uint(v: 2019-09-18T12:00:00.000000000Z)
// Returns 1568808000000000000

Calculate the duration between two timestamps

Flux doesn't support mathematical operations using time type values. To calculate the duration between two timestamps:

  1. Use the uint() function to convert each timestamp to a Unix nanosecond timestamp.
  2. Subtract one Unix nanosecond timestamp from the other.
  3. Use the duration() function to convert the result into a duration.
time1 = uint(v: 2019-09-17T21:12:05Z)
time2 = uint(v: 2019-09-18T22:16:35Z)

duration(v: time2 - time1)
// Returns 25h4m30s

{{% note %}} Flux doesn't support duration column types. To store a duration in a column, use the string() function to convert the duration to a string. {{% /note %}}

Retrieve the current time

Current UTC time

Use the now() function to return the current UTC time in RFC3339 format.

now()

{{% note %}} now() is cached at runtime, so all instances of now() in a Flux script return the same value. {{% /note %}}

Current system time

Import the system package and use the system.time() function to return the current system time of the host machine in RFC3339 format.

import "system"

system.time()

{{% note %}} system.time() returns the time it is executed, so each instance of system.time() in a Flux script returns a unique value. {{% /note %}}

Normalize irregular timestamps

To normalize irregular timestamps, truncate all _time values to a specified unit with the truncateTimeColumn() function. This is useful in join() and pivot() operations where points should align by time, but timestamps vary slightly.

data
    |> truncateTimeColumn(unit: 1m)

{{< flex >}} {{% flex-content %}} Input:

_time _value
2020-01-01T00:00:49Z 2.0
2020-01-01T00:01:01Z 1.9
2020-01-01T00:03:22Z 1.8
2020-01-01T00:04:04Z 1.9
2020-01-01T00:05:38Z 2.1
{{% /flex-content %}}
{{% flex-content %}}
Output:
_time _value
2020-01-01T00:00:00Z 2.0
2020-01-01T00:01:00Z 1.9
2020-01-01T00:03:00Z 1.8
2020-01-01T00:04:00Z 1.9
2020-01-01T00:05:00Z 2.1
{{% /flex-content %}}
{{< /flex >}}

Use timestamps and durations together

Add a duration to a timestamp

The experimental.addDuration() function adds a duration to a specified time and returns the resulting time.

{{% warn %}} By using experimental.addDuration(), you accept the risks of experimental functions. {{% /warn %}}

import "experimental"

experimental.addDuration(d: 6h, to: 2019-09-16T12:00:00Z)

// Returns 2019-09-16T18:00:00.000000000Z

Subtract a duration from a timestamp

The experimental.subDuration() function subtracts a duration from a specified time and returns the resulting time.

{{% warn %}} By using experimental.subDuration(), you accept the risks of experimental functions. {{% /warn %}}

import "experimental"

experimental.subDuration(d: 6h, from: 2019-09-16T12:00:00Z)

// Returns 2019-09-16T06:00:00.000000000Z