DuckDB Internals: Why is DuckDB Fast? (17 minute read) (opens in new tab)

DuckDB is fast because it runs in-process, avoids server/client data movement, and combines columnar storage, query optimization, predicate pushdown, vectorized execution, and row-group pruning to scan only the data it needs. This post explains how DuckDB turns SQL into an executable plan and why its storage and Parquet-reading model make analytics feel unusually fast on a single machine.