Output · Files

Write Parquet

Saves the table as a compressed Parquet file that reloads fast here, in DuckDB, pandas or Spark. Good for large in-between results.

Also known as: Columnar export

How it works

Type the Parquet file name (output.parquet by default) and pick a Location; blank means the project folder. Compression is Snappy by default, with Gzip, Zstd or None as alternatives. The write fails if the file already exists unless you tick Overwrite if the file already exists. Column types are kept as they are, so the file reloads with the same schema in a Parquet Reader, DuckDB, pandas or Spark. The written file is passed on downstream as a File.

Inputs and outputs

Settings

{
  fileName: string
  directory?: string
  compression: "snappy"|"gzip"|"zstd"|"uncompressed"
  overwrite?: boolean
}

Example

A long cleaning stage feeds several reports. Write its result to clean-orders.parquet with Overwrite ticked, and start each report pipeline from a Parquet Reader on that file instead of repeating the cleaning. Choose Zstd when the file goes over a slow link and size matters more than write speed.

More in Files

• Write CSV — Saves the table as a CSV file. It can create a new file, replace one (keeping a backup) or append to it; the delimiter, header and quoting are up to you.
• Write Excel — Writes one or more tables into named sheets of an Excel workbook. It can add to an existing workbook and keep its other sheets.
• Write JSON — Saves the table as a JSON file: one array of objects, or one object per line.
• Write XML — Saves the table as an XML file with one element per row. Both element names are up to you.
• Write HTML — Saves the table as a plain HTML page with one table and an optional title. For a styled report, use Write Report.
• Write Geo File — Saves a table with geometry as GeoJSON, GeoPackage, Shapefile or GeoParquet, ready to open in QGIS or ArcGIS. GeoParquet takes lon/lat data only.
• Write Locra Table — Saves the table with its column formats into one .ddtable file, so a colleague can pick it up in another project and see it printed the same way.