Well, you can try and run MySQL or Postgre off a RAM drive, but I suspect you won't get close to this result. And then your data is not on a reliable storage media.
Can't talk about MySQL or PostgreSQL, but with Oracle I am pretty sure you can get very much close to this result with cached data. And this is without using the in-memory option. However, talking about it withouth any experiments to prove a point is just speculation. Memory vs Disks changes a lot performance-wise.
It was expressly forbidden in the software contract to benchmark Oracle back in the 80s.
It's forbidden to publish the benchmarks, not to make them. And it's because most users are rubes who can't tune 2 databases at the same time.
With the ClickHouse OLAP db I'm limited by memory bandwidth.
I believe you're conflating the name with the actual contents of the post. The demo uses the MemSQL columnstore, which is disk-based and leverages memory only for indexes, metadata, query processing etc.