Recommended Import Methods

When importing data from other systems to DuckDB, there are several considerations to take into account. We recommend importing using the following order:

1. For systems which are supported by a DuckDB scanner extension, it's preferable to use the scanner. DuckDB currently offers scanners for MySQL, PostgreSQL, and SQLite.
2. If there is a bulk export feature in the data source system, export the data to Parquet or CSV format, then load it using DuckDB's Parquet or CSV loader.
3. If the approaches above are not applicable, consider using the DuckDB appender, currently available in the C, C++, Go, Java, and Rust APIs.
4. If the data source system supports Apache Arrow and the data transfer is a recurring task, consider using the DuckDB Arrow extension.

Methods to Avoid

If possible, avoid looping row-by-row (tuple-at-a-time) in favor of bulk operations. Performing row-by-row inserts (even with prepared statements) is detrimental to performance and will result in slow load times.

Bestpractice Unless your data is small (<100k rows), avoid using inserts in loops.