[kthejoker2]

Also Druid, HBase, Vertipaq (engine behind PowerBI), Redshift, Azure SQL DW, etc

Columnar compression is a really interesting engineering problem

[nicoburns]

Also notable is the Postgres column store extension.

Not as fancy / performant as the dedicated columns store databases, but it allows you mix and match row-tables with column-tables which is pretty nice.

[einpoklum]

Yes it is, and I've written academically about this. For example: https://is.gd/9wwjjf

[shrumm]

ClickHouse is another favourite

[einpoklum]

Clickhouse is a columnar system, yes, but is not a full-fledged DBMS. Specifically, I don't think it can join tables.

[NotSammyHagar]

memsql (which was in there for new sql).

[einpoklum]

Eh... not quite. It's in-memory representation is row-based. It seems it uses columnar secondary storage. At least - that's what it says here: https://en.wikipedia.org/wiki/MemSQL