DuckDB is one of my favourite projects of late.

Some is a little rough around the edges but it has extremely quickly replaced much more complicated setups for me. It's fast and very simple and pairs beautifully with having a bunch of data just in parquet files.

https://duckdb.org/

When do we need columnar queries? I never really found a need. Yes I used AWS Redshift, but used it like a Postgres db.

Every group by boils down to be columnar. When doing analysis you normally do a lot of grouping/slicing/dicing. True, traditional DBs can do this and more modern one will support alternative storage engines and index modes to support that kind of queries.

I was downvoted for my question, but was an honest question. This was what I needed to know. Thanks a lot.

Lower query times provide for quicker iterations.