I have no Hadoop, no HDFS. Just looking for the easiest way to export some PG tables into Parquet format for testing--need to determine what kind of space reduction we can get before deciding whether to look into it more.
Any suggestions on particular tools? (PG 12, Linux)
For simple exporting, the simplest thing is a single-node instance of Spark.
You can read parquet files in Postgres using https://github.com/adjust/parquet_fdw if you so desire but it does not support writing as parquet files are basically immutable.