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Why we lost Uber as a user

postgresql.org

131–140 of 310 posts

Re: Why we lost Uber as a user

#131

Sounds like postgres needs to support pluggable storage engines. I am sure Uber (and many others) would have paid some license fee to someone who developed a storage engine that fixed this use case. Think of how much it cost them to switch...

Yea would be amazing to see an innodb backend for PG!

( I'll let myself out ;)

Re: Why we lost Uber as a user

#133
I see some comments call this a "very specific user case". This is not. Pretty much every major web project is going to have tables like that. User sessions are just one example. Sure, you can design around this, but it is a problem and no design is going to make it completely go away.

Re: Why we lost Uber as a user

#134
post #119
post #76

Earlier quoted context omitted.

Google, too.

Google's hosted CloudSQL (a hosted &customized MySQL solution) had tons of connection drop issues. Last incident it took them 72+hrs to resolve and they had no idea what and why caused it (the resolution was a side effect from another issue that resolved for some other custom complains.)

That was 1st gen CloudSQL right? 2nd Gen CloudSQL seems much more similar to running your own MySQL server. (Both the pros and cons of that)

Re: Why we lost Uber as a user

#135

The PoststgreSQL project never fails to impress me. I know that there are some use cases which are not currently covered by it versus alternatives, but I have consistently got the feeling that everybody involved in the project is supremely professional and interested in building an excellent database – and the focus is on how to work to fix these use cases, instead of pointless mudslinging. Class act.

To be fair though... It DID take a user on the scale of Uber to find and report and migrate away because of the problem.

Re: Why we lost Uber as a user

#137
post #59

Earlier quoted context omitted.

In this case, Fabian's CV (linked from his GitHub profile, linked from his HN profile) does claim MySQL experience - correctly capitalized. But yes, I also get suspicious when people can't spell a technology correctly. For example, anyone who has spent time reading some documentation will know that Lua is capitalized in title case, and not written LUA.

Really? I will claim you will not meet many engineers who know more about Tcl than I do, and I can't remember whether it's TCL or Tcl. The absence of that knowledge has not impeded me from editing the Tcl interpreter itself. I am not convinced such pedantic measure of spelling is an accurate predictor of knowledge, to me it sounds more like elitism.

In Lua's case I agree that spelling is a predictor, but only because if you ever type LUA somewhere in the internet there is a 100% chance of someone showing up to correct you :) Its actually a bit funny.

Re: Why we lost Uber as a user

#138

Earlier quoted context omitted.

Mysql eats and corrupts data by design. For a company responding to real time events in physical world, that can be a big issue. I know they're trying to improve their defaults lately, but a lot of weird behaviour remains. And you don't have to be an expert DBA to know that choosing a technology known for silent data corruption is risky.

>Mysql eats and corrupts data by design. I'd like to have a source on that, would help shutdown a lot of MySQL discussions if true.

The docs describe a lot of ways data can be corrupted if you don't have the right configuration and database engine:

https://dev.mysql.com/doc/refman/5.7/en/constraint-invalid-d...

Re: Why we lost Uber as a user

#139
post #7

Earlier quoted context omitted.

Yes, I have a lot more respect for this than say MongoDb which claims to be great at everything.

For the kind of stuff Uber stores, they may actually be doing it wrong (given what that Postgre mailing list post says) because that is one hell of an ugly use case for any DB. I would have tried solving it by loading a dual E5v4 server full of 3TB and a slew of SSDs for L2ARC+ZIL under ZFS: more SSDs > bigger SSDs because the absolute worst case SSD performance that any and all SSDs suffer from is random reads (not…

> Uber switching to MySQL over Postgre is rather scary, I wouldn't want to be a Uber investor right now.

I guess you wouldn't have wanted to be a GOOG investor either? Most of their early revenue was from AdWords on MySQL.

Re: Why we lost Uber as a user

#140
Oh what a shame, I wonder who'll miss the other most? An industry-changing multi-billion dollar company, with a massive user base. Or an open source database company?

Postgres sucks anyways, mongo is much better.

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