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PostgreSQL 9.4 Released

postgresql.org

131–140 of 189 posts

Re: PostgreSQL 9.4 Released

#131
post #111

Earlier quoted context omitted.

People here have a problem with it because it is a technically poor solution, even among nosql databases. The main problems are: 1. Historically mongodb was distributed with completely unsafe defaults. It was insane to use it with any data you actually cared about. Once you toggle on the safety features most of the vaunted performance goes away. 2. It doesn't actually scale that well despite claims that it does. The…

You know what I don't like. People who complain about technologies they've never used. 1. This was NEVER an issue for 99.999% of people. The drivers all had the default set to FSYNC_SAFE. 2. It DOES scale the way it claims. It just doesn't have unlimited scalability and guess what no product does.

1. So then the problem they had was they didn't get the performance they expected since the benchmarks were done with different settings to juice the numbers? There is no upside to arguing this one, Mongo loses one way or the other. Can't play them both.

2. I haven't seen anyone say that Mongo scales in an unlimited fashion. You said that. I think what they might be saying is that it doesn't scale well enough to pay for the trade-offs from using it. If you aren't running a system that can be composed of somewhat-interrelated documents, you're gonna have a bad time.

Re: PostgreSQL 9.4 Released

#132
post #93

Earlier quoted context omitted.

Only someone with a poor understanding of the industry would think that. Mongo is killing it in the enterprise and their partnerships with Teradata et al is only going to cement their position for likely decades to come. Plus MongoDB's pluggable engine approach will definitely breath some new life into it.

This is exactly right. I can't believe how snide and ignorant a few of the commenters are (except I can because it's the same folks with the same FUD every time). MongoDB isn't standing still and it is getting better and better with every release. Not to mention there are 100's of massive projects running on MongoDB with success. Something about MongoDB really drives the Postgres community (and certain NoSQL DB fans)…

"This just in, Mongo is still in the hype cycle in the slow-moving enterprise space! Obviously after having handily crushed the todo list and twitter clone verticals, they want to expand their influence into mega corporations' dev shops who are tired of dealing with shitty Oracle DBAs. Back to you, Chuck."

Re: PostgreSQL 9.4 Released

#134

Earlier quoted context omitted.

How do you cluster in postgresql? Serious question, my prefer noSQL is cassandra and clustering is pretty easy. I ask this question every year and postgresql have not deliver this. If there is any, there are hardly any documentation on it.

Clustering is really, really hard. Cassandra is one of the better ones out there, but you have to deal with its data model and weird consistency promises (which however weird you think they are, are weirder) The correct way to cluster also changes dramatically depending on your use case. Sure there are things like RAC that promise to make it just work, but those don't scale more than a few nodes. Mongo is kind of the…

> Mongo is kind of the worst in this - it clusters in one weird way, has bad tooling, and subtly destroys your data at scale.

I'm genuinely interested. How does Mongo corrupts data? Thanks.

Re: PostgreSQL 9.4 Released

#135
post #111

Earlier quoted context omitted.

People here have a problem with it because it is a technically poor solution, even among nosql databases. The main problems are: 1. Historically mongodb was distributed with completely unsafe defaults. It was insane to use it with any data you actually cared about. Once you toggle on the safety features most of the vaunted performance goes away. 2. It doesn't actually scale that well despite claims that it does. The…

You know what I don't like. People who complain about technologies they've never used. 1. This was NEVER an issue for 99.999% of people. The drivers all had the default set to FSYNC_SAFE. 2. It DOES scale the way it claims. It just doesn't have unlimited scalability and guess what no product does.

All the drivers default to FSYNC_SAFE? Maybe the Java one didn't get the memo. It's set to ACKNOWLEDGED by default.

https://github.com/mongodb/mongo-java-driver/blob/master/src...

I like Mongo. And until I really learned about it, I got bitten by the default a few times. Personally I use REPLICA_ACKNOWLEDGED when running in a cluster and FSYNC when writing to a single node.

Re: PostgreSQL 9.4 Released

#136
post #44
post #5

Like every year before, the Postgres team has blessed us with an early christmas present. And like every release post before, I'd like to use this opportunity to say thanks to the team for the awesome job they are doing year after year. It's not just the database itself (and that's awesome on its own right), but it's also all the peripheral stuff: The documentation is seriously amazing and very complete, the tools th…

Since you're planning on doing some conceptual work with JSONB, just a heads upon one gotcha - duplicate properties are not allowed. I.E.: { task: "do stuff", task: "do other stuff" } which sometimes is useful when you have front-end data with an N-number of entries but its a form that serializes to an object instead of an array. There are other use cases too.

Okay, I'll bite.

What, exactly, do you think should happen if you have an object of the form

    { task: "do stuff", task: "do other stuff" }
? Objects in JSON are key-value pairs. A single key goes to a single value. Instead, you should map task to an array of values.

Re: PostgreSQL 9.4 Released

#137
post #111

Earlier quoted context omitted.

People here have a problem with it because it is a technically poor solution, even among nosql databases. The main problems are: 1. Historically mongodb was distributed with completely unsafe defaults. It was insane to use it with any data you actually cared about. Once you toggle on the safety features most of the vaunted performance goes away. 2. It doesn't actually scale that well despite claims that it does. The…

You know what I don't like. People who complain about technologies they've never used. 1. This was NEVER an issue for 99.999% of people. The drivers all had the default set to FSYNC_SAFE. 2. It DOES scale the way it claims. It just doesn't have unlimited scalability and guess what no product does.

2 is wrong. Mongos shits all over itself after only a few nodes and moderate traffic. It's balancing is incredibly broken and will kill a small cluster very quickly.

Source: tried to use it at scale

Re: PostgreSQL 9.4 Released

#138
It looks like PostgreSQL is on track to slowly succeed MySQL as the de-facto open source database.

Microsoft tentatively seems to be settling on them as the preferred RDBMS for non-Windows platforms [1]:

> Within ASP.NET 5 our primary focus is on SQL Server, and then PostgreSQL to support the standard Mac/Linux environment.

I use EF+SQL Server and they're very much complementary and provide an excellent developer experience. NHibernate+SQL Server is woeful unless you want to use the loosely-typed Criteria stuff. NH's LINQ provider is terrible and it gets confused at the drop of a hat (call Distinct and then OrderBy? "I'm sorry Dave, I'm afraid I can't do that"). At this point I'm convinced only MS know how to write LINQ providers that won't fall over the moment you try to do something useful with them.

Microsoft writing a LINQ provider for PgSql is a great thing for running .NET code on non-Windows platforms.

[1] http://blogs.msdn.com/b/adonet/archive/2014/12/02/ef7-priori...

Re: PostgreSQL 9.4 Released

#139
post #126

Earlier quoted context omitted.

Vernor Vinge's A Deepness in the Sky actually has a role described as "programmer archaeologist": http://en.wikipedia.org/wiki/A_Deepness_in_the_Sky#Interstel...

That is, btw, an absolutely fantastic distant future sci-fi novel. Among the best of all time. (Vinge doesn't consistently product books that good, but man that one is great.)

Just bought it because that premise sounds amazing. Amazon has it listed as "Zones of Thought series Book 2". Should I read book 1 before reading this?

Re: PostgreSQL 9.4 Released

#140

Earlier quoted context omitted.

Clustering is really, really hard. Cassandra is one of the better ones out there, but you have to deal with its data model and weird consistency promises (which however weird you think they are, are weirder) The correct way to cluster also changes dramatically depending on your use case. Sure there are things like RAC that promise to make it just work, but those don't scale more than a few nodes. Mongo is kind of the…

> Mongo is kind of the worst in this - it clusters in one weird way, has bad tooling, and subtly destroys your data at scale. I'm genuinely interested. How does Mongo corrupts data? Thanks.

The most infuriating way is that it will roll back its oplog on an election, and sometimes throw away confirmed writes.

Mongos does weird magic as well when it gets confused, and will confirm writes to the wrong shards during "interesting" situations.

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