join.inner() function

join.inner() performs an inner join on two table streams.

The function calls join.tables() with the method parameter set to "inner".

Function type signature

(<-left: stream[A], as: (l: A, r: B) => C, on: (l: A, r: B) => bool, right: stream[B]) => stream[C] where A: Record, B: Record, C: Record

Parameters

left

Left input stream. Default is piped-forward data (<-).

right

(Required) Right input stream.

on

(Required) Function that takes a left and right record (l, and r respectively), and returns a boolean.

The body of the function must be a single boolean expression, consisting of one or more equality comparisons between a property of l and a property of r, each chained together by the and operator.

as

(Required) Function that takes a left and a right record (l and r respectively), and returns a record. The returned record is included in the final output.

Examples

Perform an inner join

import "sampledata"
import "join"

ints = sampledata.int()
strings = sampledata.string()

join.inner(
    left: ints,
    right: strings,
    on: (l, r) => l._time == r._time,
    as: (l, r) => ({l with label: r._value}),
)