[inglor]

Not the downvoter - but I can totally understand the downvote.

The fact your anecdotal evidence is that you did not lose any data doesn't mean the internet is not full of people who have lost data with Mongo. I have no idea what your workload is, but my experience with data loss and uptime has not been as great as yours.

I'm not for bashing things either - I think there are cases Mongo might be appropriate, I just don't like countering claims with "it worked for me on this one data set". If it drops writes for one out of 100 people that's still a big reason to avoid it if that's a big concern for you. As for "these issues have been fixed" you're welcome to open the issue tracker - no one at Mongo claims all of these issues have been fixed (then again, PostgreSQL has open issues too) so your claim that "these issues have been fixed" is kind of odd...

[functional_test]

I only brought that up to counter his claim that data loss is inevitable. Of course my anecdote doesn't mean it's not common =) But anecdotes are all anyone else has, and every time I've read one about someone losing data, they either hadn't read the documentation, or just didn't understand the semantics of what they were doing. Very very rarely, especially these days, has it been an actual DB bug (though I will admit I got Mongo to core one time on 2.4 doing a compaction).

And it's a little disingenuous to point at the issue tracker -- as you say, everyone has open issues. The specific things that are mentioned though have been fixed: writes are checked by default now, the global lock has been broken up into per table locks, etc. There may still be common issues that aren't being addressed, but if there are, I'm not aware of them.

[thezilch]

Anecdotes are not all one has. We have researchers, and it seems you might have missed yesterday's https://aphyr.com/posts/322-call-me-maybe-mongodb-stale-read... (or previous posts on the matter). This link debunks the value of RTFM for Mongo or misunderstanding the API or the rarity of the bug being the DB.

[LunaSea]

I think that it is disingenuous to say that because a fuzzer found certain obscure scenarios where there are issues that automatically everyone is going to be affected by it and that the database has no merits.

Also, if I have to choose a datastore, although marketing shouldn't be important, funding is and MongoDB has had some huge funding rounds in the past. This gives me a lot more confidence in choosing it.

[functional_test]

I did miss that actually. Thank you for responding to me with something real. I'll reply again once I've had the opportunity to take a look.

[nemothekid]

If I say "its inevitable that you will get into an accident while drunk driving" and you say "I've been drunk driving for years with 100% no accidents" I would assume you are being dense.

[functional_test]

That is not a valid comparison, and as someone who has been affected by drunk drivers, I take great issue with your trivialization of a serious issue.

But I'd expect nothing less from HN.

[nemothekid]

How is it not valid? There are documented tests of exactly how and why the database loses data (just like there are studies showing the effects of alcohol), and you have claimed that "it's fine, because it never happened to me". You said the claim was baseless when it wasn't - there is another very popular HN post recently documenting how someone ran a test, proved the database was losing data, and the issue was closed as wontfix (but later reopened). Is aphyr's entire article baseless (and the one he wrote 2 years ago).

In the face of actual data, and reproducible tests - isn't saying something like "well it didn't happen to me" dense?

The comparison might be insensitive, so excuse me for hurting your feelings, but I don't see how its invalid.

A more apt analogy then would be someone saying "My database runs with 100% uptime for 3 years, so there is no reason for me to keep backups"

[functional_test]

Ah yes, downvotes outnumbering real responses. Classic HN.