[SOLVED] Which NoSQL DB is best fitted for OLTP financial systems?

Which NoSQL DB is best fitted for OLTP financial systems?

We're designing an OLTP financial system. it should be able to support 10.000 transactions per second and have reporting features.

So we have come to the idea of using:

a NoSQL DB as our main storage
a MySQL DB (Percona server actually) making some ETLs from the NoSQL DB for store reporting data

We're considering MongoDB and Riak for the NoSQL job. we have read that Riak scales more smoothly than MongoDB. And we would like to listen your opinion.

Which NoSQL DB would you use for a OLTP financial system?
How has been your experience scaling MongoDB/Riak?

Solution

TigerBeetle: https://tigerbeetle.com/

TigerBeetle redesigns the distributed database storage engine and consensus protocol for the OLTP workload. This solves the problem of OLTP write contention to unlock three orders of magnitude more performance than a general purpose (OLGP) database.