# A streaming job writes a new 4 KB Parquet file every few seconds

Canonical URL: <https://datadriven.io/problems/a-streaming-job-writes-a-new-4-kb-parquet-file-every-few-sec-1f86a009>

Domain: Pipeline Design · Difficulty: medium

## Problem

A streaming job writes a new 4 KB Parquet file every few seconds. After a month the table has millions of tiny files and every query spends its time opening files, not reading data. Fix the file layout without dropping the streaming ingest.

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