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MongoDB shares jump more than 30% in $192M IPO

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Re: MongoDB shares jump more than 30% in $192M IPO

#192
post #99

Earlier quoted context omitted.

In certain environments, it is better to fail then to have data that isn't immediately consistent. Finance and healthcare are two such systems. Availability is not always paramount. https://en.wikipedia.org/wiki/Database_transaction https://en.wikipedia.org/wiki/Atomicity_(database_systems)

They only guarantee consistency as long as you don't use them over a network, i.e. communications with the database are always reliable. But once you do use them over a network - CAP theorem comes in and forces you to either use something like two-phase commit or no promises of consistency. Which is the opposite of what his post implied, like there is CAP consistency with those databases. But there never was! Althoug…

Wait, CAP theorem just says that you have to sacrifice availability of you want Consistency and Partition tolerance.

Re: MongoDB shares jump more than 30% in $192M IPO

#193
post #165

Earlier quoted context omitted.

In general NoSQL solutions are optimized for certain use-cases at the detriment of others. If you're looking for a general purpose database, then RDBMSs like PostgreSQL are your best bet. So that said, when comparing NoSQL solutions, ending up with an apples versus oranges comparison is almost inevitable.

The funny thing is PG will outperform most NoSQL solutions as NoSQL store for vast majority of use cases.

Well, I for one think PostgreSQL is overrated.

The number one reason for why people want NoSQL is horizontal scaling and for that PostgreSQL is terrible, with all available solutions being hacks that don't work.

Re: MongoDB shares jump more than 30% in $192M IPO

#194
post #140

Earlier quoted context omitted.

I'm continuously amazed when I hear about mongodb in use. Not over say postgres, I get that there are nosql advantages, but over literally any other nosql option. https://en.wikipedia.org/wiki/Poe%27s_law is the term you're looking for...

Which NoSQL would you prefer over mongo?

Couchbase has a pretty nice mobile sync system, with clients for both Android and iOS.

Re: MongoDB shares jump more than 30% in $192M IPO

#196

> "Most applications today run on a database technology that was introduced in the 1970s," Ittycheria said. "In the '70s, I was using a rotary phone to have a phone conversation. So people are looking for a modern, scalable and flexible platform." It's like a weird version of the Turing test where you have to decide whether someone's speaking seriously or in jest when they talk about NoSQL. https://www.youtube.com/wa…

Yes dumb argument. That YouTube video was the first thing I thought of when I read the sentence.

Let's scrap everything that was invented in the 70's or before.

Re: MongoDB shares jump more than 30% in $192M IPO

#197
post #165

Earlier quoted context omitted.

The funny thing is PG will outperform most NoSQL solutions as NoSQL store for vast majority of use cases.

Well, I for one think PostgreSQL is overrated. The number one reason for why people want NoSQL is horizontal scaling and for that PostgreSQL is terrible, with all available solutions being hacks that don't work.

I second this. Mongo clusters are easy to manage, and the aggregation pipeline or MapReduce engines do wonders on a sharded cluster with tons of data. That's the selling point of mongo for me.

Re: MongoDB shares jump more than 30% in $192M IPO

#198
post #132

Earlier quoted context omitted.

Most RDBMSs can do key-value stores very well now. Yep, all of MongoDB is just one bullet point on Postgres's list of features. Anyone spending on money on it ought to be hauled before the shareholders and given a talking to on fiduciary responsibility...

>just one bullet point Tell me again how Postgres can seamlessly do horizontal scaling and synchronous replication?

Synchronous replication was added in 9.1 and much improved in 9.6? pglogical[0] works pretty well for me under 10 but I have no production experience with bdr[1].

[0]: https://www.2ndquadrant.com/en/resources/pglogical/ [1]: https://www.2ndquadrant.com/en/resources/bdr/

Re: MongoDB shares jump more than 30% in $192M IPO

#199

Earlier quoted context omitted.

Which NoSQL would you prefer over mongo?

Couchbase has a pretty nice mobile sync system, with clients for both Android and iOS.

The problem I found with couch is handling user permissions at database level. Except for that detail, it's one of the best databases I've ever used.

Re: MongoDB shares jump more than 30% in $192M IPO

#200

Earlier quoted context omitted.

> Sparse heterogeneous data is often the type of data stored in NoSQL dbs. I still can't imagine what sparse heterogeneous data exists in the world that makes sense to store. Any type of querying or processing requires some kind of structure (even if implicit in the code) which you can just put in different table structures. You have to make sense of data to process it and that kind of implies a structure, doesn't it…

Customer Analytical Record / Feature Engineering Store One customer column, tens of thousands of attribute columns. If you need everything about a customer it is a single, O(1) fetch operation which makes it perfect for driving chat bots, call centres, websites, operational decisioning engines, dashboards etc. Almost every large company will have one of these. You can't really do it in relational systems properly bec…

What would the attribute columns consist of? My experience has been with named columns defined individually by humans, of which I've never seen more than a few hundred; how do you get tens of thousands? Are they a different kind of thing?
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