sqlite2parquet lets you generate parquet files from a sqlite database. It's available as a library and as a CLI application; they're feature-equivalent, so use whichever is most convenient. See here for some notes on archiving sqlite databases as parquet files. The code is in the public domain.
Install it like this:
$ cargo install sqlite2parquetIf you use the library directly, you'll probably want to remove the CLI-related
dependencies, so set default-features = false in your Cargo.toml.