Documentation

Fill null values in data

This page documents an earlier version of InfluxDB OSS. InfluxDB 3 Core is the latest stable version.

Use the fill() function to replace null values with:

data
  |> fill(usePrevious: true)

// OR

data
  |> fill(value: 0.0)
  • Copy
  • Fill window

Fill empty windows of time

The fill() function does not fill empty windows of time. It only replaces null values in existing data. Filling empty windows of time requires time interpolation (see influxdata/flux#2428).

Fill with the previous value

To fill null values with the previous non-null value, set the usePrevious parameter to true.

Values remain null if there is no previous non-null value in the table.

data
  |> fill(usePrevious: true)
  • Copy
  • Fill window

Given the following input:

_time_value
2020-01-01T00:01:00Znull
2020-01-01T00:02:00Z0.8
2020-01-01T00:03:00Znull
2020-01-01T00:04:00Znull
2020-01-01T00:05:00Z1.4

fill(usePrevious: true) returns:

_time_value
2020-01-01T00:01:00Znull
2020-01-01T00:02:00Z0.8
2020-01-01T00:03:00Z0.8
2020-01-01T00:04:00Z0.8
2020-01-01T00:05:00Z1.4

Fill with a specified value

To fill null values with a specified value, use the value parameter to specify the fill value. The fill value must match the data type of the column.

data
  |> fill(value: 0.0)
  • Copy
  • Fill window

Given the following input:

_time_value
2020-01-01T00:01:00Znull
2020-01-01T00:02:00Z0.8
2020-01-01T00:03:00Znull
2020-01-01T00:04:00Znull
2020-01-01T00:05:00Z1.4

fill(value: 0.0) returns:

_time_value
2020-01-01T00:01:00Z0.0
2020-01-01T00:02:00Z0.8
2020-01-01T00:03:00Z0.0
2020-01-01T00:04:00Z0.0
2020-01-01T00:05:00Z1.4

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The future of Flux

Flux is going into maintenance mode. You can continue using it as you currently are without any changes to your code.

Read more

New in InfluxDB 3.2

Key enhancements in InfluxDB 3.2 and the InfluxDB 3 Explorer UI is now generally available.

See the Blog Post

InfluxDB 3.2 is now available for both Core and Enterprise, bringing the general availability of InfluxDB 3 Explorer, a new UI that simplifies how you query, explore, and visualize data. On top of that, InfluxDB 3.2 includes a wide range of performance improvements, feature updates, and bug fixes including automated data retention and more.

For more information, check out: