# Two consumers read the same streaming aggregation

Canonical URL: <https://datadriven.io/problems/two-consumers-read-the-same-streaming-aggregation-the-finan-fce1bd01>

Domain: Pipeline Design · Difficulty: medium

## Problem

Two consumers read the same streaming aggregation. The finance dashboard reports daily revenue and is audited monthly; reruns must produce identical history. The operations dashboard shows events-per-second the engine is processing and is used to detect lag. The section's rule is to name the consumer first, then the time domain: event time for finance (auditable, reproducible), processing time for operations (records what the engine saw). Pick the time domain on the canvas by splitting the existing aggregation into two transforms, one named for event-time bucketing feeding the finance consumer, one named for processing-time bucketing feeding the operations consumer.

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