Clickhouse is by far the leading open source columnar SQL data warehouse at this point. We have had strong open source operational SQL DBs for many years (MySQ

Clickhouse is by far the leading open source columnar SQL data warehouse at this point. We have had strong open source operational SQL DBs for many years (MySQL, Postgres), but no open source systems that mirrored closed source MPP columnstore until clickhouse. Its interesting that it took "this long" for a strong open source SQL DW to emerge.