[funcDropShadow]

What is the point of using MongoDB with multi-document ACID transactions? Enabling durability in MongoDB is usually costly enough that you can't find a performance benefit compared to Postgres. With JSONB support in PostgreSQL, I dare say, it can express anything that MongoDB can express with its data model and query language. That leaves scalability as the only possible advantage of MongoDB compared to PostgreSQL. And the scalability of MongoDB is rather restrictive, compared to e.g. Cassandra.

And I would never trust a database that has such a bad track record, regarding durability as MongoDB, although I admit that PostgreSQL had theoretical problems there as well in the past.

[spmurrayzzz]

I actually agree with you on the point about multi-document tx's, I wouldn't choose mongo solely for that feature. Its nice to have maybe for the niche use case in your nosql workload for when its beneficial. But the point I was originally making was that nosql stacks are not fundamentally incompatible with most of the features or safety constraints offered by other RDBMS.

> And I would never trust a database that has such a bad track record, regarding durability as MongoDB

I can't comment on your own experience obviously, but I've been using mongo since 2011 in high throughput distributed systems and it's been mostly great (one of my current systems averages ~38 million docs per minute, operating currently at 5 9s of uptime).

Definitely some pain points initially in the transition to WiredTiger, but that largely was a positive move for the stack as a whole. Durability fires have not plagued my experience thus far, not to say they won't in the future of course.

As you noted, Postgres has had its own headaches as well. Finding out that all their literature claiming their transactions were serializable when they were in fact not serializable could be considered a mar on their record. But much like mongo, they have been quick to address implementation bugs as they are found.

[funcDropShadow]

> I can't comment on your own experience obviously, but I've been using mongo since 2011 in high throughput distributed systems and it's been mostly great (one of my current systems averages ~38 million docs per minute, operating currently at 5 9s of uptime).

> Definitely some pain points initially in the transition to WiredTiger, but that largely was a positive move for the stack as a whole. Durability fires have not plagued my experience thus far, not to say they won't in the future of course.

Good to read that some are actually using MongoDB to their benefit. Indeed I have encountered problems with durability in the wild. Nothing, that I would like to repeat. But as always for a specific use case the answer is: it depends. For a general advice with what to start a new project I would select PostgreSQL in 10 out of 10 cases, if a database server is actually required.