Data Import
Partial Reading
DuckDB supports projection pushdown into the Parquet file itself. That is to say, when querying a Parquet file, only the columns required for the query are read. This allows you to read only the part of the Parquet file that you are interested in. This will be done automatically by DuckDB.  
DuckDB also supports filter pushdown into the Parquet reader. When you apply a filter to a column that is scanned from a Parquet file, the filter will be pushed down into the scan, and can even be used to skip parts of the file using the built-in zonemaps. Note that this will depend on whether or not your Parquet file contains zonemaps.  
Filter and projection pushdown provide significant performance benefits. See [our blog post “Querying Parquet with Precision Using DuckDB”](https://duckdb.org/2021/06/25/querying-parquet) for more information.