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Why we lost Uber as a user

postgresql.org

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Re: Why we lost Uber as a user

#251

Post by schoen »

SQLite wrote: post #247
Grishnakh wrote: post #172

Earlier quoted context omitted.

Also, I'm pretty sure most of us are mispronouncing MySQL: IIRC, "My" (the Finnish name of his daughter) is pronounced like English "Me".

I don't speak Finnish. But I did once hear David Axmark pronounce My's name, and to my ear it sounded like "Mih" - an "M" followed by a short vowel similar to the vowel in "bit". In other words, My's name is the same as Mitt Romney's first name, just without the "t" at the end.

You might want IPA [ɪ]. (But another comment in this thread suggested [y], a sound that English doesn't have, and which is close in several ways to English [i] in "me" or [ɪ] in "bit".)

Re: Why we lost Uber as a user

#252

Post by chc »

Grishnakh wrote: post #171
Roboprog wrote: post #152

Earlier quoted context omitted.

Suggested edit: s/This is total bullshit/Perhaps you overlooked something:/. Otherwise, this would have been a good comment, I think.

This is one thing I like about HN's system: it lets me edit posts for a limited period. I'll sometimes bang out a post like the above, with a rather negative opening line like that and hit "submit". Then a minute later I'll realize I need to tone that down some, so I'll go edit it, as you suggest here. Unfortunately some shitty web forums don't allow you to edit posts at all, but I do appreciate ones which do allow e…

HN also lets you set a delay before a comment appears, if you're like me and tend to catch mistakes more easily on the page than in the composition box. It's called "delay" on your settings page.

Re: Why we lost Uber as a user

#253

Post by CamperBob2 »

sluukkonen wrote: post #197
Grishnakh wrote: post #172

Earlier quoted context omitted.

Also, I'm pretty sure most of us are mispronouncing MySQL: IIRC, "My" (the Finnish name of his daughter) is pronounced like English "Me".

The y is pronounced like the ü in über.

Actually it's more like the 'j' in Eyjafjallajökull.

Re: Why we lost Uber as a user

#254

Post by astrodust »

assface wrote: post #130
babuskov wrote: post #28

Earlier quoted context omitted.

> The PoststgreSQL project never fails to impress me. Except the name is a bit clunky and hard to write ;)

It's called Postgres because it was the second DBMS that Stonebraker started after Ingres. So it's "post Ingres", or "post gres"

Then they made it speak SQL, so it was called PostgreSQL, which some might confuse as "Postgre SQL".

Re: Why we lost Uber as a user

#255

Post by astrodust »

stouset wrote: post #210
jrochkind1 wrote: post #149

Earlier quoted context omitted.

I'm pretty sure Uber has enough money and enough developers to configure MySQL to not do any of that.

You can't configure MySQL to not do "any" of that. You can certainly make it better, but there simply aren't options to configure away all of the boneheadedness. There are also tons of hidden gotchas that exist in, for example, the query planner. It can be extremely fickle and suddenly switch from a performant query plan to a terrible one that creates unindexed temporary tables and sorts them or joins against them. O…

You're thinking there's databases out there that are flawless, that never corrupt data, but that's garbage. They all do to a degree. They're also subject to being corrupted by hardware failures that aren't related to software.

Anyone with a huge production database running under load is going to have ways of mitigating these problems. Tumblr manages with MySQL, they open-sourced some of their tools like JetPants (https://github.com/tumblr/jetpants) to help build huge datasets.

So maybe Uber made a call and said "we can deal with intermittent corruption problems, we can recover from those, so long as the performance is better because a reputation for being slow is something we can't recover from". Life is all about trade-offs.

Re: Why we lost Uber as a user

#256

Post by neves »

I've already read 2 very long about this issue, but this very succinct text is really way better than any of others. The best computer programming article I've read in months.

Re: Why we lost Uber as a user

#257

Post by xfalcox »

mrfusion wrote: post #19

I don't understand if they mean that foreign key relationships are contributing to the problem. If so is it possible to turn off foreign key constaints during a big load? Would it be worth removing indexes during a big load? (Currently fighting with an etl that can't get above 500 rows / second even after using copy from)

Dropping constraints when doing ETL is common. You can create then after and rollback if problems arise.

Re: Why we lost Uber as a user

#258

Post by duaneb »

angelbob wrote: post #160
methehack wrote: post #145

Does anyone else think the scenario in the explanation is an unreasonable request to make of a relational database? I think that if you've created a design that requires you to update a 50K row table 500 times a second that itself is heavily indexed and used heavily in joins, you have a software design problem more than a database problem. I wouldn't expect any database to handle that and am surprised that mysql does…

You're not wrong. But mostly we haven't collectively agreed that relational databases aren't great for highly-indexed rapid-update join tables. I think we will at some point. That's the primary original use case for a lot of NoSQL, and the reason Twitter had so much trouble with relational databases. But these are cultural understandings, and those move slowly. Also, we're poorly (collectively) equipped to handle sub…

How has NoSQL addressed join tables? All the approaches I've seen are much, much slower than with a traditionally vertically scaled relational database—or by moving away from joining altogether—it's traditionally been the twin pressures of scale and replication that force people to move to a distributed database.

Re: Why we lost Uber as a user

#259

Post by kaitai »

sluukkonen wrote: post #197
Grishnakh wrote: post #172

Earlier quoted context omitted.

Also, I'm pretty sure most of us are mispronouncing MySQL: IIRC, "My" (the Finnish name of his daughter) is pronounced like English "Me".

The y is pronounced like the ü in über.

A tip that works for some: lips to say "oooo" (like an owl, or someone seeing something shiny for the first time), tongue to say "eeee". Well, worth a try.
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