CockroachDB is made up of several layers to implement SQL and transactions on top of a distributed key-value store: https://www.cockroachlabs.com/docs/stable/ar

CockroachDB is made up of several layers to implement SQL and transactions on top of a distributed key-value store: https://www.cockroachlabs.com/docs/stable/architecture/overview.html#layers https://www.cockroachlabs.com/docs/stable/architecture/overv... TiDB has a similar architecture: https://www.pingcap.com/docs/architecture/ https://www.pingcap.com/docs/architecture/