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2026-04-10 17:41
Apache Parquet File Anatomy: Row Groups, Column Chunks, Pages, and Metadata Explained 🧱📦
If you use Spark, Athena, Iceberg, Snowflake, DuckDB, or Pandas, you’ve probably worked with Parquet hundreds of times. But most of us first learn Parquet as a simple rule of thumb: it’s columnar, compressed, and great for analytics. That’s true, but it leaves out the most interesting part — why Parquet performs so well in the first place.
Under the hood, a Parquet file is not just a blob of comp...