docs-v2/content/flux/v0/stdlib/internal/promql/join.md

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promql.join() function	`promql.join()` joins two streams of tables on the **group key and `_time` column**. See [`experimental.join`](/flux/v0/stdlib/experimental/join/).	flux_v0_ref name parent identifier promql.join internal/promql internal/promql/join	201

promql.join() joins two streams of tables on the group key and _time column. See experimental.join.

Important: The internal/promql package is not meant for external use.

Function type signature

(fn: (left: A, right: B) => C, left: stream[A], right: stream[B]) => stream[C] where A: Record, B: Record, C: Record

{{% caption %}} For more information, see Function type signatures. {{% /caption %}}

Parameters

left

({{< req >}}) First of two streams of tables to join.

right

({{< req >}}) Second of two streams of tables to join.

fn

({{< req >}}) Function with left and right arguments that maps a new output record using values from the left and right input records. The return value must be a record.