# A meal-kit subscription company has two raw inputs: a Postgres orders database where rows accumulate

Canonical URL: <https://datadriven.io/problems/a-meal-kit-subscription-company-has-two-raw-inputs-a-postgr-a289621f>

Domain: Pipeline Design · Difficulty: medium

## Problem

A meal-kit subscription company has two raw inputs: a Postgres orders database where rows accumulate all day until a job processes the chunk, and a Kafka topic of mobile-app clickstream events where each event flows through as it arrives. Apply the two-rhythms framing this section just taught and name each source's rhythm by setting its slaFreshness label. The Postgres source travels in scheduled chunks (a daily-tier batch label like < 24h), and the Kafka source travels continuously (a real-time-tier label like real-time or < 1min). The two sources must end up with distinct labels so the diagram does not collapse the two rhythms onto one cadence.

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