Documentation

Statements

A statement controls execution.

Statement      = [ Attributes ] StatementInner .
StatementInner = OptionAssignment
                | BuiltinStatement
                | VariableAssignment
                | ReturnStatement
                | ExpressionStatement
                | TestcaseStatement .

Return statements

A terminating statement prevents execution of all statements that appear after it in the same block. A return statement is a terminating statement.

ReturnStatement = "return" Expression .

Expression statements

An expression statement is an expression where the computed value is discarded.

ExpressionStatement = Expression .
Examples of expression statements
1 + 1
f()
a

Testcase statements

A testcase statement defines a test case.

Testcase statements only work within the context of a Flux development environment.

TestcaseStatement = "testcase" identifier [ TestcaseExtention ] Block .
TestcaseExtention = "extends" string_lit

Test cases are defined as a set of statements with special scoping rules. Each test case statement in a file is considered to be its own main package. In effect, all statements in package scope and all statements contained within the test case statement are flattened into a single main package and executed. Use the testing package from the standard library to control the pass failure of the test case.

Test extension augments an existing test case with more statements or attributes. A special function call, super(), must be made inside the body of a test case extension. All statements from the parent test case will be executed in its place.

Basic testcase for addition
import "testing"

testcase addition {
    testing.assertEqualValues(got: 1 + 1, want: 2)
}
Example testcase extension to prevent feature regression
@feature({vectorization: true})
testcase vector_addition extends "basics_test.addition" {
    super()
}

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InfluxDB 3.9: Performance upgrade preview

InfluxDB 3 Enterprise 3.9 includes a beta of major performance upgrades with faster single-series queries, wide-and-sparse table support, and more.

InfluxDB 3 Enterprise 3.9 includes a beta of major performance and feature updates.

Key improvements:

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  • Consistent resource usage
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Preview features are subject to breaking changes.

For more information, see:

Telegraf Enterprise now in public beta

Get early access to the Telegraf Controller and provide feedback to help shape the future of Telegraf Enterprise.

See the Blog Post

The upcoming Telegraf Enterprise offering is for organizations running Telegraf at scale and is comprised of two key components:

  • Telegraf Controller: A control plane (UI + API) that centralizes Telegraf configuration management and agent health visibility.
  • Telegraf Enterprise Support: Official support for Telegraf Controller and Telegraf plugins.

Join the Telegraf Enterprise beta to get early access to the Telegraf Controller and provide feedback to help shape the future of Telegraf Enterprise.

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View the release notes
Download Telegraf Controller v0.0.6-beta

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On May 27, 2026, the latest tag for InfluxDB Docker images will point to InfluxDB 3 Core. To avoid unexpected upgrades, use specific version tags in your Docker deployments.

If using Docker to install and run InfluxDB, the latest tag will point to InfluxDB 3 Core. To avoid unexpected upgrades, use specific version tags in your Docker deployments. For example, if using Docker to run InfluxDB v2, replace the latest version tag with a specific version tag in your Docker pull command–for example:

docker pull influxdb:2