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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

#171
post #132

Earlier quoted context omitted.

RDBMS makes sense for most applications. Most applications store data that can be fit to the relational model. Most applications aren't big data or data mining OLAP. Most RDBMSs can do key-value stores very well now. Most applications also care more about consistency over availability, which is what RDBMSs do (CAP theorem). Many NoSQL data stores choose availability and partitioning and sacrifice consistency (i.e., "…

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?

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

#172

> "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…

I know there's quite some aversion to NoSQL around here, and generally I don't care much as I'm seldomly dealing directly with databases. But recently, I've been exposed to a fairly big and complex SQL one with several references between entities and lots, lots of X_has_Y tables. This makes me think that with growing complexity (which seems to be a general trend), NoSQL databases seem more practical at some point, or…

i got downvoted in another thread for saying nosql has a lot of advantages in reducing work like not having to worry about carefully creating indexes when joining billion row tables. someone replied you dont need indexes. i replied I dont know how you plan on running joins on billion row tables in postgress without indexes. got downvoted again.

I bet they are still waiting for that join....

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

#173
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?

Literally any other. I'm unaware of any alternative so unreliable.

But I do think http://www.scylladb.com/ is great.

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

#174

Earlier quoted context omitted.

Meanwhile almost all of those applications are written in languages 20+ years old (Ruby, Java, PHP, Javascript.. Python is almost 30)

while the languages may be old...they're constantly updated... php 7 is lightyears ahead of 5 and 4 was just a joke.. Python 3 same.. just because somethingn is new/old doesn't make it better/worst I mean - many devs swear by Vim which is like 40 years old.. is sublime text better because it's newer? (I use sublime..but I admire those who've jumped into vim for the productivity boost that brings).

That’s exactly the point though. It’s not like we’re plopping a floppy from Oracle into every machine running a modern SQL db.

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

#175
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?

Cassandra is a pretty good alternative if you're looking for excellent write speeds and scalability.

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

#176

Per crunchbase they raised their last funding round on a pre-money valuation of $1.6 billion. Since the market cap now is less than that valuation, why is the coverage saying this is a big success? It seems to me like this is a down round of some sort. Does anyone know if I am missing something here? Or does this type of down round not really affect the employees common stock?

That really depends on the terms of their last investment round. As far as I know those haven't been disclosed. I would suspect that the investor in the last round is compensated with more shares, probably something similar to if he had invested at a 1.1 billion instead of 1.6 billion valuation. Maybe not though. Depends on the terms.

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

#177
post #106

This means the company absolutely positively mispriced the offering. The company could have successfully raised nearly 30% more money.

That's not how it works. When you're shopping around your IPO before going public, you need to get commitments from institutional investors to buy your stock at IPO at a particular price. Just because people will start buying at +30% shortly after IPO does not mean you can get investors to commit to a 30% higher IPO price beforehand.

That's exactly how it works. What you are describing is the standard IB B.S. speech. It has been debunked multiple times, starting from the time of DLJ.

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

#178
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?

Aerospike for low-latency small row sizes, HBase for everything else.

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

#179
post #64

Earlier quoted context omitted.

You don't seem to know this, but no traditional RDBMSs actually provide CAP consistency, for that they would have to use at least two-phase commit or something, but they don't. So, they all are noCAP databases. Electronic health or financial records are way safer in a proper eventually consistent database, like orders of magnitude safer, but everyone just takes the risk with some insurance at best to cover the losses…

> "no traditional RDBMS actually provide CAP consistency, for that they would have to use at least two-phase commit https://docs.microsoft.com/en-us/sql/t-sql/language-elements... > If the transaction committed was a Transact-SQL distributed transaction, COMMIT TRANSACTION triggers MS DTC to use a two-phase commit protocol to commit all of the servers involved in the transaction. If a local transaction spans two or m…

Thanks for pointing out. Oracle has distributed transactions too.

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

#180
post #31

Earlier quoted context omitted.

Sure. The most direct argument against that is that Postgresql jsonb is just non-relational data support in a first class relational DB, which is pretty great, so to an extend you get the best of both worlds, though I'm sure you can find a case where it's not quite optimal vs some nosql db. This talk is a pretty nifty perf overview: https://www.percona.com/live/e17/sessions/high-performance-j... That said, if you kno…

PostgreSQL JSONB doesn't have a dedicated driver though i.e. you can't do partial updates via the JDBC/ODBC drivers. Which means you can't use it for any big data/analytics use cases. MongoDB has fantastic client libraries e.g. Spark, Java.

The JDBC driver for postgres fully supports partial updates with JSONB, though?
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