This project is a lightweight analytical database written in C++, which is compact in size, free from external dependencies, and does not operate as a separate process, akin to an analytical version of SQLite. DuckDB offers a rich SQL dialect, supporting features such as JOIN, aggregation, window functions, and direct querying of CSV and JSON files. Although it does not have a performance advantage in terms of scale, it is fully capable of handling data analysis at the billion-level scale, focusing on being small, light, and sufficient.