Data Engineering12 July 20268 min read

Parquet File Format Deep Dive: Row Groups, Dictionary Encoding, and Snappy Compression

Why Parquet files achieve 80%+ compression ratios over CSV: inspecting columnar binary structure, footer metadata, and dictionary encoding.

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Parquet File Format Deep Dive: Row Groups, Dictionary Encoding, and Snappy Compression Cover

Inside the Parquet Binary Structure

Parquet organizes data into Row Groups, encoding distinct strings into dictionary key arrays.

References & Further Reading:

Apache Parquet Documentation

#Databricks #SQL

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