The CockroachDB documentation says their SQL implementation is layered on top of their K/V interface: https://www.cockroachlabs.com/docs/stable/architecture/overv...
This would make it similar to TiDB/TiKV and FoundationDB.
Here's and old article from VoltDB insisting that layering SQL on pure K/V forfeits too much performance: https://www.voltdb.com/blog/2015/04/01/foundationdbs-lesson-...
Edit: And a response: https://news.ycombinator.com/item?id=15505194
The CockroachDB documentation says their SQL implementation is layered on top of their K/V interface: https://www.cockroachlabs.com/docs/stable/architecture/overv...
This would make it similar to TiDB/TiKV and FoundationDB.
Here's and old article from VoltDB insisting that layering SQL on pure K/V forfeits too much performance: https://www.voltdb.com/blog/2015/04/01/foundationdbs-lesson-...
Edit: And a response: https://news.ycombinator.com/item?id=15505194