Right now I (well, we, my team) uses Hbase and in a previous project I used Cassandra. These are very high scale systems where we need replicated writes (for

Right now I (well, we, my team) uses Hbase and in a previous project I used Cassandra. These are very high scale systems where we need replicated writes (for durability and availability), we need horizontal scalability and performance (write heavy or mixed read/write workloads) trumps transactionality. There aren't a lot of writeups about performance benchmarks between NoSQL and SQL but as far as I know it's not even close to the same ballpark: https://www.scylladb.com/2021/01/21/cockroachdb-vs-scylla-benchmark/#Benchmarking https://www.scylladb.com/2021/01/21/cockroachdb-vs-scylla-be... With something like Cassandra you get read after write guarantees that I think you don't get with read replicas and SQL databases but I'm not too familiar with the latest there. Also once you start breaking up your SQL databases into shards you lose all SQL goodness across shards (like joins and other properties). So no free lunches basically. I'd love for there to be something fast, scalable, queryable, transactional etc. etc. Honestly I haven't looked in a while but every open source SQL solution I've seen in the past that claimed to be durable/reliable/scalable doesn't actually do that under failure modes like NoSQL does and pretty much loses either performance or other guarantees or both. Ofcourse NoSQL doesn't solve some of these problems, but at least you know what you're getting into ;)