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Does everyone hate MongoDB?

blog.serverdensity.com

21–30 of 159 posts

Re: Does everyone hate MongoDB?

#21
post #15
post #10

Earlier quoted context omitted.

Well of course it's not exciting, but that's exactly the kind of examples I like hearing about because now I know I should always have detailed logging off. Anyways, I'm sure a lot of us would appreciate it if you wrote about your experiences, regardless of how mundane they are.

It looks like you want to leave detailed logging off ...

Haha whoops. Edited my previous comment.

Re: Does everyone hate MongoDB?

#22

We've been using MongoDB in production for our main content store at Conversocial for over a year now. We've gone from 1.8 to 2.0 to 2.2 and we're happy. We have ~400gb of data, 220 million documents all on Amazon's SSD instances. We have definitely had our moments where we've screamed that we hate Mongo and are going to rip it out. That's normally where we've overlooked a detail of how it works... and we've had this…

Could you elaborate on the things that MongoDB brings to the table versus a database like MySQL? If you assume that the entire dataset fits in memory for both MongoDB and MySQL, as well as SSD backing for both, what particular advantages does MongoDB have for you in production?

Re: Does everyone hate MongoDB?

#23
post #8

Does everyone hate MongoDB? - 25 Sept 2012 Headline Problem: Too many people are ranting about MongoDB. Mistake: Too few data points. Overly defensive of MongoDB. Comments: You should probably learn more about Riak. The "From MongoDB to Riak" is light on details but isn't really hand-waving. The author is saying that having a masterless database results in less fretting. http://wiki.basho.com/Riak-Compared-to-MongoDB…

Now that Couchbase Server 2.0 is beta, it's a reliable alternative to MongoDB. Same JSON goodness, different set of user stories. (hint: less rants). Get the beta download here: http://www.couchbase.com/couchbase-server/beta

Re: Does everyone hate MongoDB?

#25
I love that MongoDb allows me to get stuff done without much fuss even when I have not figured out the final data requirements. I have been using RDBMS + ORM ( Hibernate) for a very long time; however I found this to be very "rigid" in a start up environment where the requirements are far from frozen. MongoDB is much more flexible and forgiving than traditional RDBMS in that respect.

Re: Does everyone hate MongoDB?

#26
post #5

> Comments: The 32 bit limit is noted (perhaps it should be a warning) on the download page but the main problem was the author did not know when writes started to fail. MongoDB uses unsafe writes by default in the sense that from the driver, you do not know if the write has succeeded without a further call to getLastError. This is because one of the often cited use cases for MongoDB is fast writes, which is achieved…

Is that the situation here with the 32-bit silent fail default? That it is a sensible default, but could be changed if it's shown that competent devs will nonetheless screw it up?

It's kind of sad that we'd need an example to show that it really could happen in every single specific case. It should be common knowledge by now that competent devs screw things up all the time.

For example, I'm sure the MongoDB devs are extremely competent. But all the same, having a database management system default to letting writes fail silently is a pretty spectacular screw-up. I can't really blame other competent devs for taking it for granted that a DBMS wouldn't do something like that.

Re: Does everyone hate MongoDB?

#27
I think it looks promising - it's not a panacea, there are things SQL works better for and there are things I can see Mongodb would really rock with.

With anything there are gotchas so you have to live and learn with em.

When I was researching Mongodb before going into it I saw forums talking about the 2gb limit on 32 bit systems; I would say the author of that article didn't see the posting - which could either be a case of not due diligence on the ins and out of the system or lack of diligence on the reference material he had originally been using to build his system.

Re: Does everyone hate MongoDB?

#28
post #2

hell no, it's been a breath of really fresh air for us, we've been building all sorts of things, no problems so far. (including logging several millions of requests per day and performing distributed map reduce for all sorts of statistical models on a tiny 3 machine "cluster" we run on AWS, I hope I never have to go back to modifying schemas again, so much simpler to run and build with this mindset)

> I hope I never have to go back to modifying schemas again

Honest question. Do you actually leverage the schemaless nature of MongoDB? Not 'worrying' about managing schemas is one thing, but actually leveraging the fact that your objects can have different fields is another. I have worked on projects that did need to store objects with different fields together but it seems to be a rare case.

From what I've seen, most projects actually have pretty standard objects with specific fields. People just don't like feeling constrained but in the end I don't think managing a schema is difficult at all. I actually like the safety and performance you get when you put in the effort.

I think the single most useful thing to see when starting a new dev job somewhere are the database schemas. If done properly, it will essentially tell you the story of that company and their data. You can think up questions and get answers such as "Is it possible for a Customer to have multiple Orders? Can a product have more than one Review?" (Stupid examples but they illustrate the kinds of relationships which are asked about all the time).

Re: Does everyone hate MongoDB?

#29
Let's not conflate "hating" (which is always pointless) with pointing out flaws in a design.

"Mongo sucks f*cking balls" is hating it. "Mongo silently does not store data in some situations" is pointing out a flaw.

It is easy to dismiss valid criticism as hate. It is also unfortunately true that some topics degenerate to flamewars on HN. Why Mongo is such catalyst is a phenomenon in itself. One that I find fascinating.

Re: Does everyone hate MongoDB?

#30
They don't all hate MongoDB, they're just singling themselves out as people we shouldn't work with. Ranting about a product without knowing much about it or even reading the documentation simply points out what type of engineer you wouldn't want to deal with.
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