I'm a PhD student in databases at CMU. Over the past few months, I've been interning at Columnar and building a community extension for DuckDB that lets you query Snowflake, Databricks, BigQuery, PostgreSQL, MySQL, and any other system with an ADBC (Arrow Database Connectivity) driver.
The extension supports querying ADBC databases directly through a read_adbc table function. It also supports using ATTACH to connect to an ADBC database and then running SELECT, INSERT, COPY, and CTAS statements as if the database were local to DuckDB.
You can install it from DuckDB by running: INSTALL adbc FROM community; LOAD adbc;
The ADBC extension is open source and available under the Apache-2.0 License. We plan to contribute this extension to the Arrow project so it can become an official ADBC library.
Give it a try, and leave feedback if you have ideas about how to make it better. Leave an issue on the GitHub repo if you hit any rough edges!