Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The Great Migration from MongoDB to PostgreSQL

infisical.com

Post reply on HN
Print view View original

141–150 of 339 posts

Re: The Great Migration from MongoDB to PostgreSQL

#141

Post by tkellogg »

finaard wrote: post #129
dangtony98 wrote: post #94

Earlier quoted context omitted.

Author of the article here! The article itself does not "complain the product is bad" but some other comments in this thread would certainly suggest so. Instead, the article says that the use-case evolved, states reasons for why MongoDB was no longer suitable (while at some point it was) and why PostgreSQL was chosen instead, and discusses the migration process involved in the transition and the results. Regarding la…

To me the article read more that PostgreSQL might have been the better choice from the beginning - but due to lack of experience in the team MongoDB was "good enough" at that point.

I recall when my team chose MongoDB ~2011, Postgres & friends didn't have JSON columns, so there was a lot of extra data modelling that probably was unnecessary.

The biggest use case for MongoDB was for huMongous data. Obvs MongoDB was a good fit, because of the name.

Re: The Great Migration from MongoDB to PostgreSQL

#142

Post by paulryanrogers »

pmarreck wrote: post #134
bradleyjg wrote: post #120

Earlier quoted context omitted.

Oracle

Oracle is a giant mess, is the sense I got from trying to work with it in the past. While I am loathe to recommend any Microsoft product, SQL Server is at least coherent, and has actual transactions like Oracle (and not just "checkpoints")

Aren't MSSQL and Oracle just doing redo logs, like MySQL?

What do you consider not actual transactions?

Postgresql keeps dead tuples in place until vacuumed, which seems optimized for rollbacks. But isn't so bad if you're inserting much more than deleting or updating.

Re: The Great Migration from MongoDB to PostgreSQL

#144

Post by LtWorf »

CuriouslyC wrote: post #87
onetimeuse92304 wrote: post #38

Ah, the old "I used a wrong product for my problem and now I complain the product is bad because it does not suit my case." defence. MongoDB is a document database. It is not supposed to be good at relations. Also lacking support with cloud providers and lacking experience with MongoDB is not MongoDB's problem, it is your poor decisionmaking. If you value those things, you should have taken it into account when you w…

If mongo is just a document database, there's really no reason to use it over elastic. The query story is slightly nicer with mongo, but we're not doing relational algebra here, right? Elastic crushes mongo at literally everything else.

ES had a bug where a syntax error in a query would send it in a weird state that would then give wrong answers to all queries until the process got rebooted. Which of course isn't fast.

I reported the issue, and thankfully I changed job and never had to deal with ES again. After a few years they contacted me to ask if the issue was still there, I said I had no idea.

I have no idea if the issue is still there.

Re: The Great Migration from MongoDB to PostgreSQL

#145

Post by LtWorf »

circusfly wrote: post #138
thiht wrote: post #56

Earlier quoted context omitted.

Postgres is not hype though. There's very few legitimate use cases for not using a RDBMS as a main data store, and Postgres happens to be the most popular nowadays, for good reasons.

I've nothing against Postgres but MySQL is a wonderful option that is likely still in far higher and heavier use, when considering open source databases.

I think it gained popularity over a decade ago, when it was faster because it was unsafe.

In the end postgres is the better one. With mysql the defaults are bad.

Re: The Great Migration from MongoDB to PostgreSQL

#146

Post by hibikir »

akie wrote: post #73

Did anyone here ever see a migration _from_ PostgreSQL/MySQL _to_ MongoDB? I've only ever seen startups pick Mongo, then regret it a few months or years down the line and migrate to a relational database. Did anyone ever see the opposite?

I've seen a couple of successful ones, but there were extremely good reasons: Most of the time we don't need scaling, but when your target Mongo cluster has a couple hundred machines, and your queries really are very simple, NoSQL is not a crazy idea. Same with DynamoDB: Sometimes it really is a very good choice, but you need a use case of the right shape. If you have an extremely good use case for your table to be in 5+ regions, the dataset has billions of rows and you have no hot keys, maybe running your own replication system really is more effort than letting AWS do it all for you.

It's just far more common for some tech lead in small company to imagine that they are going to be bigger than Netflix, than for someone to start conservatively with a RDBMS, and realize that suddenly they have hundreds of millions of users and some kinds of data where the relational bits don't matter.

Re: The Great Migration from MongoDB to PostgreSQL

#147

Post by lloydatkinson »

dangtony98 wrote: post #94
onetimeuse92304 wrote: post #38

Ah, the old "I used a wrong product for my problem and now I complain the product is bad because it does not suit my case." defence. MongoDB is a document database. It is not supposed to be good at relations. Also lacking support with cloud providers and lacking experience with MongoDB is not MongoDB's problem, it is your poor decisionmaking. If you value those things, you should have taken it into account when you w…

Author of the article here! The article itself does not "complain the product is bad" but some other comments in this thread would certainly suggest so. Instead, the article says that the use-case evolved, states reasons for why MongoDB was no longer suitable (while at some point it was) and why PostgreSQL was chosen instead, and discusses the migration process involved in the transition and the results. Regarding la…

I have noticed in recent times comments on here have been getting more and more like this. An article I posted a few weeks ago got the same treatment even though I iterated multiple times the same points as I anticipated these kinds of comments from people that didn’t read it fully.

Re: The Great Migration from MongoDB to PostgreSQL

#148

Post by thih9 »

onetimeuse92304 wrote: post #55
thih9 wrote: post #41

Earlier quoted context omitted.

To be fair, Mongodb’s pr team did their best to present it as the solution to all problems. > In 2012, 10gen’s VP of Corporate Strategy Matt Asay argued “there will remain a relatively small sphere of applications unsuitable for MongoDB … the majority of application software that developers write will be in use cases that are better fits for MongoDB and other NoSQL technology … Those functions that really help a comp…

To be fair, almost all product PR teams do the same. I just ignore most of what they say in favour of my own opinion that I try to build based on reading actual technical documentation, experimenting with the product, etc. Anybody who makes tech decisions based solely on what PR teams say is naive and incompetent at best.

> To be fair, almost all product PR teams do the same.

No, mongodb’s PR approach and results were largely uncommon at the time. They didn’t advertise directly but instead targeted and amplified dev communities - as detailed in the article linked earlier.

The result was that people not associated with mongodb talked about mongodb at various dev conferences and in blog posts. People didn’t want to listen to PR teams then too, but they followed their peers.

Re: The Great Migration from MongoDB to PostgreSQL

#149

Post by kstrauser »

circusfly wrote: post #138
thiht wrote: post #56

Earlier quoted context omitted.

Postgres is not hype though. There's very few legitimate use cases for not using a RDBMS as a main data store, and Postgres happens to be the most popular nowadays, for good reasons.

I've nothing against Postgres but MySQL is a wonderful option that is likely still in far higher and heavier use, when considering open source databases.

In my mind, MySQL no longer exists. It’s a weird Oracle thing that I wouldn’t touch with a lineman’s pole. MariaDB is what happened after MySQL disappeared.

Re: The Great Migration from MongoDB to PostgreSQL

#150

Post by J_Shelby_J »

madsbuch wrote: post #111
kqr wrote: post #69

Earlier quoted context omitted.

But isn't there a point before which "just use sqlite" is more appropriate advice?

I am curious on this. Why do you think SQLite is simpler than Postgres? and in what setting is that the case? Sqlite comes with the headache of managing an attached volume.

Building an mvp or a single container app.

I’m actually trying to get Postgres to work like this right now.

SQLite being embedded is simpler to use and more performant in this environment as there is no IPC overhead.

Post reply on HN