DuckDB Internals: Why Is DuckDB Fast? (Part 1)

DuckDB is an in-process analytical SQL database that has rapidly become one of the most widely adopted databases due to its ease of use, small footprint (under 20 MB), and exceptional performance on single-node systems. Unlike server-based databases that require network serialization and deserialization of results, DuckDB runs as a library within applications, eliminating this overhead and enabling it to query multi-gigabyte files in seconds without requiring clusters or infrastructure setup. The article begins a three-part series explaining DuckDB's speed through its architecture, including in-process execution, columnar storage, vectorized execution, and optimized parallelism.