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Jepsen Disputes MongoDB's Data Consistency Claims

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Re: Jepsen Disputes MongoDB's Data Consistency Claims

#101

You can tell a lot about a developer by their preferred database. * Mongo: I like things easy, even if easy is dangerous. I probably write Javascript exclusively * MySQL: I don't like to rock the boat, and MySQL is available everywhere * PostgreSQL: I'm not afraid of the command line * H2: My company can't afford a database admin, so I embedded the database in our application (I have actually done this) * SQLite: I'm…

As someone who chose MySQL and provides direction to developers who really like Postgres, and who also uses Postgres for fun, I do find myself having to both defend MySQL as a prudent option and convince them that I know anything at all about Postgres or computer science. :)

I tend to find people who argue with me against MySQL bring up things that haven't been true in a long time such as Unicode or NULL handling.

I'd probably choose Postgres over MySQL for a new project just to have the improved JSON support, but there's upsides to MySQL too:

- Per-thread vs per-process connection handling

- Ease of getting replication running

- Ability to use alternate engines such as MyRocks

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#102

You can tell a lot about a developer by their preferred database. * Mongo: I like things easy, even if easy is dangerous. I probably write Javascript exclusively * MySQL: I don't like to rock the boat, and MySQL is available everywhere * PostgreSQL: I'm not afraid of the command line * H2: My company can't afford a database admin, so I embedded the database in our application (I have actually done this) * SQLite: I'm…

HAHAHAH The RabbitMQ one got me. Have your upvote, sir.

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#103
post #87
post #12

Earlier quoted context omitted.

Some readers might not be familiar with that particular meme: https://m.youtube.com/watch?v=b2F-DItXtZs IMHO it perfectly describes the hype-reality disconnect at the early days of MongoDB. Yeah it was that bad. Mongo has improved since, the hype has toned down and the NoSQL space is more crowded these days.

The damage is done. I have to use this crap at work when we should be using an SQL database. We have been planning a migration since before I started a year and a half ago. I won't be surprised if we are still on Mongo in another year and a half.

Fantasy: "Don't use special database features (by which I mean, like, any features) and make sure our ORM supports a ton of different datastores because we might want to change to a different database at some point and don't want to be tied to this one."

Reality: Three app rewrites later plus another application written talking to the same DB, and the database is still the same.

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#104

In the circles I run in, MongoDB is regarded as a joke and the company behind it as basically duplicitous. For example, they still list Facebook as their first user of MongoDB on their website, for example, but there is no MongoDB use in Facebook hasn't been for years (it came in only via a startup acquisition). I had the misfortune to use MongoDB at a previous job. The replication protocol wasn't atomic. You would f…

> but there is no MongoDB use in Facebook hasn't been for years

Are you sure?

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#105
post #100

Earlier quoted context omitted.

RabbitMQ stores your data, right? Then it's a database! That's pretty much all it takes. A flat file, memory-store, SQL DB, Document store, any of them can be databases if that's where you stick your data! But also no, RabbitMQ and Kafka and the like are clearly message buses and though they might also technically qualify as a DB it would be a poor descriptor.

> Kafka and the like are clearly message buses and though they might also technically qualify as a DB ksqldb is actually a database on top of this. The thing is that they have an incrementally updated materialized view that is the table, while the event stream is similar to a WAL ("ahead of write logs?" in this case). Because eventually you can't just go over your entire history for every query.

[deleted]

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#106

Earlier quoted context omitted.

This might be a stupid question, but surely no one thinks of RabbigMQ as a database right? I’ve used it from 2012 to 2018 extensively, including using things like shovels to build hub spoke topologies, however not once did I think of it as anything but a message broker. Did I miss something huge?

RabbitMQ stores your data, right? Then it's a database! That's pretty much all it takes. A flat file, memory-store, SQL DB, Document store, any of them can be databases if that's where you stick your data! But also no, RabbitMQ and Kafka and the like are clearly message buses and though they might also technically qualify as a DB it would be a poor descriptor.

Oh ho ho ho. What weird things we use as a databases. I remember when I first started out as a consultant developer we were using a CMS as our data repository because someone thought that was a good idea. (It wasn't). The vendor was flown in from the states to help troubleshooting. I will never forget how he looked at me when I had to explain to him why we made so many nodes in the content tree, it was because we were using the CMS as a repository.

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#107

Earlier quoted context omitted.

I've heard MySQL (well, MariaDB, really) has improved a lot in recent years, but I still can't imagine why I'd ever choose it over Postgres for a professional project. Is there any reason? It used to be that bargain basement shared-hosting providers would only give you a LAMP stack, so it was MySQL or nothing. But if you're on RDS, Postgres every time for my money.

mysql's admin tools are still far superior than what's available for postgres

What tools are these? Curious as a Postgres user

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#108

This has been a known issue for a while: https://hackingdistributed.com/2013/01/29/mongo-ft/ MongoDB: Broken By Design

This is a good of the HN MDB hate: everything referenced has been addressed long before 2013. It was a new DB then and early adopters should know what they’re getting into

Re: Jepsen Disputes MongoDB's Data Consistency Claims

#109

You can tell a lot about a developer by their preferred database. * Mongo: I like things easy, even if easy is dangerous. I probably write Javascript exclusively * MySQL: I don't like to rock the boat, and MySQL is available everywhere * PostgreSQL: I'm not afraid of the command line * H2: My company can't afford a database admin, so I embedded the database in our application (I have actually done this) * SQLite: I'm…

What if they prefer an XML database (like basex, exist, marklogic)?
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