Documentation

Check if a value exists

Use the Flux exists operator to check if a record contains a key or if that key’s value is null.

p = {firstName: "John", lastName: "Doe", age: 42}

exists p.firstName
// Returns true

exists p.height
// Returns false

If you’re just getting started with Flux queries, check out the following:

Use exists with row functions ( filter(), map(), reduce()) to check if a row includes a column or if the value for that column is null.

Filter null values

from(bucket: "db/rp")
    |> range(start: -5m)
    |> filter(fn: (r) => exists r._value)

Map values based on existence

from(bucket: "default")
    |> range(start: -30s)
    |> map(
        fn: (r) => ({r with
            human_readable: if exists r._value then
                "${r._field} is ${string(v: r._value)}."
            else
                "${r._field} has no value.",
        }),
    )

Ignore null values in a custom aggregate function

customSumProduct = (tables=<-) => tables
    |> reduce(
        identity: {sum: 0.0, product: 1.0},
        fn: (r, accumulator) => ({r with
            sum: if exists r._value then
                r._value + accumulator.sum
            else
                accumulator.sum,
            product: if exists r._value then
                r.value * accumulator.product
            else
                accumulator.product,
        }),
    )

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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 3.4

Key enhancements in InfluxDB 3.4 and the InfluxDB 3 Explorer 1.2.

See the Blog Post

InfluxDB 3.4 is now available for both Core and Enterprise, which introduces offline token generation for use in automated deployments and configurable license type selection that lets you bypass the interactive license prompt. InfluxDB 3 Explorer 1.2 is also available, which includes InfluxDB cache management and other new features.

For more information, check out: