[threeseed]

"Mature" doesn't make it necessarily better. I have had catastrophic data losses with Oracle and Teradata and none with Cassandra or MongoDB.

And I would disagree that Mongo is a "toy". We use it as part of our core EDW and we have petabytes of data in our data lake. No issues what so ever.

[takeda]

Can't coment on your experience with Oracle and Teradata, but the danger with MongoDB is that it has non-catastrophic data corruption.

One that you don't even realize until you compare the data with canonical source.