There's more to Singularity studies than Kurzweil - <AUTHOR> http://www.sentientdevelopments.com/2010/08/its-not-all-about-ray-theres-more-to.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+SentientDevelopments+%28Sentient+Developments%29&utm_content=Google+Reader <comment><USER3> I think Kurzweil, not unlike Chomsky, seems like a generally fascinating figure to discuss (early success, strong opinions). His popularity (both positive and negative) can be attributed to a fascination with the character more so than his exact position on one topic or another.

The one thing that I wish he would talk about more is his work in "nutrition, health, and lifestyle" [1]. He seems to make a lot of money off recommendations that aren't commonly accepted in the medical community (he, himself, ingests "250 supplements, eight to 10 glasses of alkaline water and 10 cups of green tea" every day). Why the disconnect with health practitioners? I don't know the guy, and shouldn't make judgement, but find it hard to avoid the thought that he's profiteering off of people's fears and ignorance.

1\. [http://en.wikipedia.org/wiki/Raymond_Kurzweil#Work_on_nutrit...](http://en.wikipedia.org/wiki/Raymond_Kurzweil#Work_on_nutrition.2C_health.2C_and_lifestyle)

<comment><USER4> His primary list of accomplishments should relieve some of your fears. That much serial entrepreneurship places him securely in the 'comfortable' category, and his continuing work seems to clear him from a profiteering motive. His transhumanist ambitions indicate a deep and sincere belief in his method, which is possibly more than most other dietitians can avow. I think the largest problem with the disconnect is the nature of his interest - <USER2> long term results that are difficult to support with standard research methods or testimonials.

<comment><USER5> Many pseudoscientific cranks are honest, earnest, and not at all profiteering. But they are still pseudoscientific cranks. What defines a crank is the practice of developing and advocating strong opinions despite a lack of supporting evidence, or in the face of conflicting evidence.

<comment><USER4> I'm not sure what you have to gain by planting a 'pseudoscientific crank' flag in a response here, but I'll address it anyways.

I don't follow Kurzweil's diet, and I haven't read any of his books, but to the best of my knowledge, Kurzweil invokes no chakras and no crystals. He doesn't promise unrealistic weight gain, and he doesn't seem to be advertising any harmful methods. He may be guilty of overselling the possible benefits of synthesizing several positive regimens (e.g., light exercise, low glycemic index, antioxidants, nutritional supplements), but, with the exception of alkaline water, I don't see any cogent criticism or glaring 'lack of supporting evidence'.

Would you care to supply a context for your tar, or did you just have an agenda?

<comment><USER5> I only meant to suggest that whether or not someone is intentionally "profiteering off of people's fears and ignorance" in andreyf's words isn't necessarily the best criterion by which to judge their credibility--and conversely, that your defenses of Kurzweil's honesty and earnestness miss the underlying point.

<comment><USER4> Your underlying point is that he isn't credible; andreyf's point is about profiteering. It's possible he wanted information on credibility, rather than the stated profiteering, but your paternalism has yet to supply any actual answers.

<comment><USER5> My underlying point isn't about Kurzweil at all. It's that sincerity doesn't excuse being a professional crank. Amateur cranks are bad enough, but professional cranks do benefit from "people's fears and ignorance" at their expense, no matter how sincere and well-intentioned they may be.

<comment><USER4> But this isn't about cranks. It's not even about Kurzweil! It's about Singularitarians that explicitly aren't Kurzweil, even.

You haven't made any points germane to the conversation here. If you'd like to place some actual points regarding Kurzweil as a crank, or tar all things Singularity with the crank label, or find an actual topic about cranks, your words may be well placed, but until then, your Gricean maxims may need some work.

<comment><USER5> Here's the conversation as I have understood it:

andreyf (<http://news.ycombinator.com/item?id=1629954>): Among other things, deems Kurzweil's nutritional theories (and commercial promotion thereof) as questionable.

You (<http://news.ycombinator.com/item?id=1631254>): Provided evidence of Kurzweil's sincerity and good motives to defend him from andreyf's criticism, as you perceived it.

Me (<http://news.ycombinator.com/item?id=1631299>): Illustrated (unclearly, I admit) a fallacy in your argument: Kurzweil's sincerity doesn't completely absolve him of being wrong, irrational, or even crackpottish about his nutrition.

I admit that I was unclear. What isn't unclear is how you responded--with repeated personal attacks, accusations of ulterior motives and "agendas", and a militant refusal to make any good faith attempt to understand anything I was trying to express. And now you pretend we weren't discussing an aside about Kurzweil's idiosyncratic nutritional views at all, as if you've forgotten how these comments were nested in the first place. You accuse me of wanting to "tar" Kurzweil, or "all things Singularity" (as if I'm blaspheming your god?) and then name-drop Grice to assure yourself of holding the intellectual high ground? Yeah, I know how these forum games are played as well as anyone. I just wanted you to know that I actually was trying to meaningfully communicate here.

<comment><USER4> You do make it quite clear you know how to play forum games...

I argued nowhere that Kurzweil is absolved of any putative wrongness, irrationality, or crackpottishness. You inserted a context that wasn't there and didn't do much to relate that context to anything else. In most books, fanatics are the ones that can't tell that not everyone is talking about their favorite topic. You could really use work on your maxim of relation.

<comment><USER5> My perception was that andreyf was concerned more with Kurzweil's possible crackpottishness than his sincerity. In that respect, _you_ are the one who has failed to apply Grice's maxims (or, in less intellectually pretentious terms, "missed the point"). Continually insulting me doesn't change that.

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER6> The disconnect is that a lot of people do not find the Singularity an appealing concept. Of his list Yudkowsky seems the only sane one to me.

"Primarily concerned with the Singularity as a potential human-extinction event, Yudkowsky has dedicated his work to advocacy and developing strategies towards creating survivable Singularities."

My pure speculation is that many people feel a very understandable sense of unease, but it gets expressed as doubting the possibility of the singularity future. As opposed to accepting it as possible but advocating that we try to avoid it, or at the very least approach it with extreme caution.

Kurzweil, on the other hand, comes across to me as very Pollyana-ish. He seems to spend very little time considering what could go wrong with a Singularity, and much more time eagerly anticipating our impending god-like future.

<comment><USER7> The majority of people, who when told of the singularity, automatically dismiss it offhand only because it has that Hollywood "scifi ridiculous" sound to it, seem a lot less sane to me than anyone on that list.

<comment><USER8> Most people have spent their lifetime watching people completely fail at predicting even the immediate future. Dismissing predictions of the singularity as scifi bullshit isn't a lack of sanity, it's basic extrapolation.

<comment><USER7> So these people think they are better predictors of the future than all the people who failed, even though they probably never made a serious prediction themselves? They believe something is never going to happen just because it hasn't happened _yet_? Sounds highly irrational to me.

<comment><USER8> There is a MASSIVE difference between "you're wrong" and "I'm right". Calling the singularity bullshit in a casual conversation is an example of the prior.

</comment></comment></comment></comment></comment><comment><USER9> A decent portion of the names mentioned in that post are signed up for cryonics: Kurzweil, Hanson, Minsky, and Yudkowsky. It makes sense in hindsight. These people put a very high upper bound on what future technology can accomplish.

Sources:

Kurzweil and Minsky: [http://en.wikipedia.org/wiki/Alcor_Life_Extension_Foundation...](http://en.wikipedia.org/wiki/Alcor_Life_Extension_Foundation#Membership)

Minsky: <http://www.alcor.org/AboutAlcor/meetsciadvboard.html#minsky>

Hanson: [http://www.overcomingbias.com/2008/12/we-agree-get- froze.htm...](http://www.overcomingbias.com/2008/12/we-agree-get-froze.html)

Yudkowsky: <http://lesswrong.com/lw/wq/you_only_live_twice/>

</comment><comment><USER10> This is a good list. It would be interesting to see a similar list of Singularity detractors. I know Jaron Lanier is one. His claim is that software in general is crap and won't be up to the task, even if the hardware is capable.

Kurzweil does not say much about software. He feels we will get everything we need by reverse engineering real brains. I think this is possible, but it's certainly not obviously true, and it's not a simple extrapolation. We could be sitting there in 2040 with gobs of computer power, and detailed maps of the brain, and just not understand how it all works. Look at the Genome today.

I saw Kurzweil speak in 2008. I thought he was compelling but certainly leaned heavily on hype about the exponential which I don't think is entirely justified: [http://www.kmeme.com/2010/07/singularity-is-always- steep.htm...](http://www.kmeme.com/2010/07/singularity-is-always-steep.html)

<comment><USER11> I agree with your post in general. However, the linked article missed the point of the key assumption of singularity: the current progress of computing power is 'only' doubling annually because of the limits of human intelligence. When machines reach human intelligence, they will take shorter and shorter time to improve themselves.

If H1, the human-equivalent generation of machines, takes one year to create H2, which doubles H1's speed and computing power, then H2 would take only 0.5 years to create H3, which would take 0.25 years to create H4, and so forth. The math series sum up to two or that the whole big bang would only take twice the amount of time for one doubling cycle (assuming that the delay caused by physical limits is negligible). IF this actually holds, then the progress when H1 is created will be way faster than the simple exponential illustrated in the article.

<comment><USER10> I agree. I did not depict The Singularity itself in my graphs, because Kurzweil generally does not either. He instead shows projected exponentials as evidence for The Singularity happening: <http://www.kurzweilai.net/the-law-of- accelerating-returns>

My first point is really just that the exponential is not hyperbolic. It's tempting to see an exponential graphs and think the value is rising against some invisible wall, like it is going to infinity. But of course it is not.

My second point was between the linear-exponential shooting skywards or the log-exponential rising incrementally which is "more real"? In the case of computer capacity I claim the incremental one is real, it reflects how we experience the increases.

None of this really speaks to whether the Singularity will happen or not. I'm just saying if it happens it won't be because of some upward surge in computing capacity just prior to The Singularity. Because no such surge is predicted.

</comment></comment></comment><comment><USER12> I am partial to von Neumann's definition, not rapture of the nerds. A reasonable definition of a singularity is a (technological) the effects of which nearly no one can predict. Examples, agriculture, the industrial revolution, the automobile, the computer. The Luddites predicted massive unemployment, not the incredible abundance we have today. The telephone was seen as a broadcast medium like radio, no device that remove space from personal communications. The computer, we all know what that did.

We dont even know what intelligence really is, so we cant predict what super intelligence is or will do. Will we become extinct? I seriously doubt it, just as most of us dont want our fellow creature to become extinct (except maybe rats an mosquitos). Will they become our curators, or will we have a symbiotic relationship with incredible consequences.

One consequence I do see is a huge augmentation in human intelligence with appliances that grow complexes directly into the brain. Imagine instance face and name recognition (my particular sub-optimal capability) or mathematical proof reasoning. Not that we think way faster, but that everything we want is at our fingertips. And built in virtual reality.

I think we are near the peak in our consumption of material goods. So the optimist in me sees a future free from meaningless work, where even the average Joe will have an IO of 200 or even 1000.

<comment><USER13> I'd like to address some of your statements if you don't mind, since I wouldn't want them spreading and used in place of actual thought...

First, let's do away with this "Rapture of the Nerds" business. It'd be funny if the comparison were at all valid: <http://www.acceleratingfuture.com/steven/?p=21>

Your first paragraph hints that you're more partial to Hanson's idea of having already undergone multiple Singularities that tremendously boost the economy.

> We dont even know what intelligence really is, so we cant predict what super > intelligence is or will do.

Paraphrasing from Yudkowsky, an intelligent system is that which implements its goals. If a superintelligent entity has goals even remotely recognizable to us, we can predict what it will do quite easily. Even if you have no idea how Chess works, just by knowing it's a game you can predict both sides will try to win.

I'm with you on brain-machine interfaces that augment our intelligence, though I would definitely say I could think faster, if not better. Just with the example of an internal calculator would help tremendously; somewhere around the order of trillions of synapses fire if you try to multiply two three-digit numbers if your head.

> So the optimist in me sees a future free from meaningless work, where even > the average Joe will have an IO of 200 or even 1000.

What do these figures even mean? One of the goals of a Yudkowsky-defined Singularity is that the AI (hopefully quickly) gets around to helping us augment our own intelligence, moving us along the path so that we can become something like how we presently are to ants, but with present us as the new ants. Not just all becoming Einstein.

</comment></comment><comment><USER5> The singularity (sorry, Singularity) has always struck me as religion in science-fiction garb: an end time is coming, eternal life is possible if you name a cryonics firm as the beneficiary of your life insurance policy, and we will soon enter either an unimaginable paradise or an unlivable hell where either humans will be totally extinct and replaced with robots or we will be immortal cyborgs, or maybe we'll "download our consciousness into computers", or something like that. There's remarkably little content, nor any real certainty, behind the hype.

It's perfectly reasonable to say that really interesting things are bound to happen when we fully understand the brain enough to build one ourselves. It's conjectural to say it'll be possible to build intelligences better than humans at the task of building intelligences (to significant degrees of recursion), and once you make that conjecture some sort of singularity is possible. (Not inevitable--there may indeed be unsurpassable barriers to any kind of intelligence. I'm talking about logical barriers like Gödel's incompleteness theorem, or the possibility that P != NP.) But there's no gain in "futurists" making empty predictions. I'd much rather hear from the people who actually try to build intelligences what they think is feasible, or the people who actually study neurology.

</comment><comment><USER14> For a less explicitly "pro-Singularity" take that still studies it seriously, the main North American AI organization (AAAI) recently convened a panel to look into which potential major societal effects of advancing AI should be taken seriously by AI researchers, and what (if anything) should be done with regards to those possibilities: <http://www.aaai.org/Organization/presidential-panel.php></comment>


Taking SolarFeeds to the next level - <AUTHOR>

Hi everyone, So I have built the largest solar news network without any advertising or large strategy. We have 300 contributors, and we are close to become the industry go-to.. How do i take this to the next level? Strategic partnerships? content partnerships? any tips would be helpful. Thanks<p>Scott www.solarfeeds.com <comment><USER2> I don't really have any specific advice, but I want to thank you for creating Solar Feeds. I'm interested in and invest in solar, and your site is one of the best energy sites on the web.

<comment><AUTHOR> thanks so much..i love hearing comments like that - its what keeps me going. thank you..

scott

</comment></comment><comment><AUTHOR> how do i "askHN"? thats what i meant to do here...</comment>


Lossy compression for optimizing animated GIFs - <AUTHOR> http://cloudinary.com/blog/lossy_compression_for_optimizing_animated_gifs

<comment><AUTHOR> This article describes how lossy compression for animated GIFs allows you to benefit from both worlds: embed animated GIFs in your site, enjoy their simplicity, and still deliver smaller files that look good. Animated GIFs smaller in file size improve the user experience of your site's visitors and helps you save on bandwidth. Cloud-based dynamic GIF manipulation URLs are included, as well as code samples for PHP, Rails, Node.js, jQuery, .Net and more.

</comment><comment><USER2> So, do they wrap gifsicle or did they wrote this from scratch?</comment>


Local-time effect on small space-time scale - <AUTHOR> http://arxiv.org/pdf/physics/0610137

<comment><USER2> That's one of the papers Global scaling theory is based on. There's a long story on how Hertmut Mueller as a researcher in Soviet Russia did some research for the gov. that was classified etc. They even had some talks on some german Uni's with some presentations. Keywords for ggl would be: \- global scaling theory \- g-com \- interplanetary communication \- communicating without el.mag. waves etc.

The papers were published in some alternative energy, bio suff, water memory etc. things german magazine. As to why aren't such to be profound findings published in a serious sci magazine, H.Mueller stated some dislikes about nature, sciam etc. magazines. They even have a site, they are prepared to educate you on this wonderful magic theory if u give them some money...

<comment><USER2> some more info: they state that their model can get info from static. check out utube links (mainly in german): [http://www.youtube.com/results?search_query=global+scaling&#...</a>

</comment></comment><comment><USER3> Has somebody just made an analogue of <http://pdos.csail.mit.edu/scigen/> for physics?

<comment><USER4> Huh... i couldn't make sense of it, but that's not saying much, given my knowledge of physics is limited to pop. sci. books. can somebody with more physics/math knowledge answer this please?

<comment><USER5> <http://arxiv.org/pdf/physics/0605064>

<comment><USER6> Still trying to make sense of this. Isn't there an app I can download or something?

</comment></comment></comment></comment><comment><USER7> I think what it's saying is that germanium semiconductor RNGs in different places happen to give the same result at the same time?

<comment><USER2> <http://en.wikipedia.org/wiki/Global_Consciousness_Project>

</comment></comment><comment><USER8> On scribd: [http://www.scribd.com/vacuum?url=http://arxiv.org/pdf/physic...](http://www.scribd.com/vacuum?url=http://arxiv.org/pdf/physics/0610137)

</comment><comment><USER9> ADD IN THE TITLE THAT IT'S A FUCKING PDF

<comment><USER10> I agree, it would've been nice if the OP had mentioned that this is a PDF in the title of the submission. However, yelling and cursing is, I think, below the level of discussion we'd like to see here on HN. A simple remark in the comment would suffice.</comment></comment>


Dinner: The Toughest Ticket in Town - <AUTHOR> http://www.gq.com/story/dinner-reservations-high-end-dining?src=longreads&utm_content=buffer0fe06&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

<comment><USER2> I cannot understand the argument Brett Martin is making.

"Surely there was a distant era in which the desire to eat someplace didn't guarantee that a thousand people like you also wanted to eat there at the same time", he begins. What era are we talking about here? Seriously, what is he referring to?

Right now, if you are in a city, you are surrounded by very good restaurants, many of which will give you a table with very little advance planning. And unless your city is on the decline, your food options are going to be better and more numerous than ever before.

To have Brett Martin's sort of problems, you'd have to insist that you're only going to eat at the most exquisite, high-end, overbooked restaurants. And in that case the tickets certainly aren't hurting your ability to find a table.

In all the hand-wringing about tickets, he never says what's actually wrong with them, except non-sequiturs such as "the same reason wearing underwear in public is different from wearing a bathing suit. Because we know it is."

Is he missing the ability to slip a discreetly folded $100 bill to the server and get preferentially seated? The ability to make a dinner reservation and then ditch it? Not every restaurant needs tickets, but the kind of place the article is about seems to benefit from them, and I cannot understand in the slightest what Martin's problem is.

Not even the title is right. Having bought a restaurant ticket once, it wasn't nearly as tough to get as, say, a ticket to a well-known band.

I've just wasted my time reading nonsensical claims about first-world problems that aren't even problems.

<comment><USER3> > _Is he missing the ability to slip a discreetly folded $100 bill to the > server and get preferentially seated?_

In my experience, even less. ~15% of what you expect to pay at the restaurant is usually good enough, but that's trial and error not a hard rule.

</comment></comment><comment><USER4> This article is against the ticketing, but I quite liked the long post explaining why they went with tickets by the guy who build the system: [http://website.alinearestaurant.com/2014/06/tickets-for- rest...](http://website.alinearestaurant.com/2014/06/tickets-for-restaurants/)

</comment><comment><USER5> I love food. My wife loves food. I don't just mean we love to go to exquisite overbooked restaurants. We raise our own vegetables, pigs, chickens (egg and meat), cook classic and experimental dishes together and enjoy all of it.

That said, I have eaten exactly once at a restaurant where the restaurant WAS the main attraction and reason for the evening.

Every other time it was for convenience, to celebrate something, just part of an evening out or on the way to some other event etc.

The author seems to be focusing exclusively on dining-as-experience establishments not the myriad of other places some of which also have fantastic food, great service, or new and interesting culinary experiences.

In my limited experience, ticketing is neither the next big thing or a big problem to be worried about.</comment>


Ask HN: Moving to Spain from the USA, any tips? - <AUTHOR>

I'm moving to Spain in the next few months and I'm trying to figure out what to do for a job. The type of visa I'm getting does not let me work locally for 1 year. I'd really like to be able to join a U.S. based startup and work remotely. Unfortunately, it seems like nobody is hiring remote operations/systems engineers.<p>Any tips? <comment><USER2> 1\. <http://www.tecnoempleo.com/>

2\. <http://www.computrabajo.es/>

3\. [http://www.amazon.com/Living-Working-Spain-Survival- Handbook...](http://www.amazon.com/Living-Working-Spain-Survival- Handbook/dp/1905303653/ref=sr_1_2?ie=UTF8&qid=1304644282&sr=8-2)

</comment><comment><USER3> Out of curiosity, why Spain? I ask as the nation has undergone quite a vicious economic cycle and their next door neighbor, Portugal, is in quite bad shape.

That said, I'm sure there is plenty of opportunity around. What sort of companies have you approached so far? There may be other firms looking to hire or you could go after some remote contract work too.

<comment><AUTHOR> My wife has always wanted to move.... I'm along for the ride. It's a beautiful country and I'm very excited to move there. We have some money in savings so we could last a few years even if the economy is crappy.

I've approached lots of startups and nobody is really interested in remote employees. I'm starting to think I should try to approach big companies but that will probably be just as difficult to break into.

There do seem to be lots of local jobs in Barcelona and Madrid but I'd rather not wait a year to get a job.

<comment><USER2> In theory, the EU Blue Card goes into effect June this year, and Spain has opted in:

<http://lexuniversal.com/en/news/10787>

Maybe you can work for a local company sooner than one year via that visa.

Which part of Spain are you moving to, and what kind of visa does your wife have?

<comment><AUTHOR> Thanks for the EU Blue Card link... I'll look into it.

We're thinking of moving to Madrid or Barcelona. We prefer Barcelona, but there seems to be a lot more work in Madrid, we'll see what happens.

Both of us are in the process of applying for a non-lucrative visa. We haven't actually submitted our application yet, which will take 3-5 months to be processed, because we're waiting on the FBI background check which takes 6 weeks.

It's quite the process to move to Spain but it'll be worth it!

</comment></comment></comment></comment><comment><USER4> Spain is probably hovering around 20% unemployment, and you won't like the pay they're offering. You'd think with all the startups doing mobile/cloud computing there would be more of a market for telecommuters. I'd keep looking and try to line up something before you leave.

</comment><comment><USER5> I'm from Spain (and glad to help) :)

If you hace general questions ask them here, or ir they are more specific feel free to drop me a line (diego -at- ducksboard.com)

The spanish startup scene is becoming more mature. I know dozens of them with with 20+ employees. Also, due to the general lack of English knowledge here, a native developer is always more than welcome.

<comment><AUTHOR> Anyone looking for awesome operations/systems engineers? :) Is there any particular city where the startup scene is better?

</comment></comment><comment><USER6> Hi Yellowbox, Do you have an idea where best to base yourself for employment in Spain? Do you or your wife speak Spanish? There is a free guide about how to successfully move to Spain, that might help you on this blog. www.mymovetospain.com

<comment><AUTHOR> We're thinking Madrid or Barcelona..... Madrid has more work I think. My wife speaks pretty good Spanish and I'm trying to learn in my free time. Thank you for the link.

</comment></comment><comment><USER7> I'm in Madrid. Drop me a line if you need anything.</comment>


Enabling JSON Document Stores in Relational Systems (2013) [pdf] - <AUTHOR> http://pages.cs.wisc.edu/~chasseur/pubs/argo-long.pdf

<comment><USER2> > ...providing all the advantages of NoSQL JSON document stores, while > providing higher performance and richer functionality (such as native joins, > and ACID guarantees instead of BASE consistency)

Seems too good to be true.

The performance impact of inserting/fetching multiple rows per object, multiple SQL joins for a single logical join, etc. would probably be significant. And indexing these tables seems to require indexing every name/value pair, not just the interesting fields. And, of course, the overhead of the translation layer itself.

Also, are relational native joins and ACID guarantees still available at scale?

<comment><USER3> Not sure about this paper, but Postgres' JSONB is quite good.

It's quite fast, you can easily use values like SQL sub-queries and you can index both everything and also specific subsets of the JSON data with expression indexes.

<comment><USER2> That's native support for the data type; this paper is about a translation layer that sits on top of the DB.

</comment></comment></comment><comment><USER4> There's an open-source implementation of a different approach to the same problem in ToroDB ([http://github.com/torodb/torodb](http://github.com/torodb/torodb)).

ToroDB creates tables dynamically, which match the types (mapped to columns) of every level of the JSON documents, obtaining a fully relational database. This is effectively "partitioning" (automatically) the documents based on their effective "type".

ToroDB actually uses PostgreSQL as its backend to store the data relationally.

Hope this information is interesting.

Disclaimer: I am one of the developers of ToroDB

</comment><comment><USER5> I find these papers from 1999 by Daniela Florescu more informative with regards to the benefits of the various schema available to map semi-structured data:

[http://dsl.serc.iisc.ernet.in/~course/TIDS/papers/daniela.pd...](http://dsl.serc.iisc.ernet.in/~course/TIDS/papers/daniela.pdf)

[http://faculty.ksu.edu.sa/mathkour/XML%20DB/A%20Performance%...](http://faculty.ksu.edu.sa/mathkour/XML%20DB/A%20Performance%20Evaluation%20of%20Alternative%20Mapping%20Schemes%20%20%281%29.pdf)

</comment><comment><USER6> [http://schemafreedb.com/demo.html](http://schemafreedb.com/demo.html) not a doc store but allows the storing of semi-structured data with a sql like query language with a json over http api.

<comment><USER7> [http://howfuckedismydatabase.com/nosql/](http://howfuckedismydatabase.com/nosql/)

<comment><USER6> I do not see how this applies. Below is an example of how you query the data. Map reduce not required

[ {"query": { "_queryId":"office-query", "sfql": "SELECT $phone.oid, $s:phone.name, $s:phone.value WHERE $s:phone.name='office'" }}, {"query": { "_queryId":"mobile-query", "sfql": "SELECT $phone.oid, $s:phone.name, $s:phone.value WHERE $s:phone.name='mobile'" }} ]

<comment><USER6> and example result is in json format. Note two queries in one request referenced by query ID.

[ { "_queryId": "office-query", "cmdname": "query", "data": [ { "phone_oid": "3", "s:phone_name": "office", "s:phone_value": "111-112-1113" }, { "phone_oid": "7", "s:phone_name": "office", "s:phone_value": "111-112-1113" } ] }, { "_queryId": "mobile-query", "cmdname": "query", "data": [ { "phone_oid": "4", "s:phone_name": "mobile", "s:phone_value": "222:223:2224" }, { "phone_oid": "8", "s:phone_name": "mobile", "s:phone_value": "222:223:2224" } ] } ]

</comment></comment></comment></comment><comment><USER8> I developed something a little bit like this when developing a profiler for JSON documents but didn't think about general purpose queries, in particular I squashed [3] to [].

</comment><comment><USER9> This seems cool, but does anybody know about possibility of using mongo query language with Relational Databases?

<comment><USER10> I have absolutely no idea what I'm talking about, but maybe a Postgres extension could be written for this? There's one for running SQL Server T-SQL in Postgres, which is absolutely nothing like Mongo, but...

<comment><USER11> This would probably be the right way to go. I even started working on a solution last year (see other comment), but got side-tracked by real-life issues.

My idea was to write a PG extension which would handle all the smarts, and expose a set of sql functions which could be called from the application side. Those functions could then be wrapped in nice client libraries to give a consistent mongo-a-like interface across languages, with the client doing the bare-minimum to shuttle data to and from the database server.

</comment></comment></comment><comment><USER12> JSON is fine in relational and NoSQL databases... until you start trying to query fields inside the JSON.

</comment><comment><USER13> XML database 2.0. Here we go again.</comment>


A Day without Programming - <AUTHOR> http://blog.filepicker.io/post/28141038384/a-day-without-programming

<comment><USER3> Hm! I find that I have to fight to find time to program.

Something like 80% of my time is spent explaining existing systems, reading bug reports, going to meetings, talking through API designs and database modeling, answering email, etc.

I would love to take a day where I did nothing _but_ program.

<comment><AUTHOR> Sounds like you work for a BigCorp

<comment><USER3> I work for a successful startup. The previous startup I worked at was much the same.

<comment><AUTHOR> Huh - well my apologies for making an assumption. I suppose it depends on the role/size of company

</comment></comment></comment></comment><comment><USER4> I fully agree. If you're a bootstrapping technical founder I'd even suggest going further and doing alternating code sprints and "other" sprints.

Last week I finally switched gears to marketing, design and biz-dev after coding core functionality for three months and it was by far the most productive week ever. I didn't touch code (other than a few bugfixes) all week and started doing press work, coming up with a distribution strategy, hiring interns etc. I should have done this much sooner and it's amazing. I'll try doing the same thing the next two weeks, I doubt not coming out with a new feature every few days is as bad as some of us engineers might think ;)

</comment><comment><USER5> I really liked this post for a couple of reasons.

First is that I know I sometimes lose sight of the end goal of a project when I start coding for weeks on end. I'll get sucked into a bug or a feature that I think is necessary and my vision for the future of the product becomes clouded.

I also relate this to the design of a product. Without taking a day to step back and try to examine your product from a different perspective, I don't think you'll ever be able to properly analyze and iterate on anything you create.

This all stems from my feelings that every engineer should also furiously work to be a good designer as well.

</comment><comment><USER6> I generally use Friday for all business related task. No programming allowed unless it's a critical bug.

I'd actually come to enjoy spending most of the day doing my finances, answering emails, cleaning out the inbox etc. All in a relaxed manner - <USER2> the weekend then takes of with a good conscience.

I highly recommend it.

</comment><comment><USER7> I do think this is a great idea, and I actually subscribe to it (although definitely don't do it). I think the higher-order problem that you touch on is that when we have a million things to do, we tend to de-prioritise those that are outside our comfort zone, regardless of how much value they could add.

</comment><comment><USER8> Good post. One thing I like to do is take a bit of my time each week and sit down with a person who has _never_ used my product. In fact, ideally they've never even heard of it. Shut off the programming-mindset and just watch an average person do their thing with your product. Some amazing insight there.

<comment><AUTHOR> Neat idea - we were looking at doing <http://www.usertesting.com/> for helping out with this

</comment></comment><comment><USER9> Totally agree. As valuable as engineering resources are, it's the little things that make people love your product.

<comment><AUTHOR> The point is, it's not just engineering resources that are valuable!

</comment></comment><comment><USER10> I've noticed that as well; it's frequently easier and more enjoyable to dig into code (or, for that matter, read things here) than to do some of the actual important work necessary for business.

</comment><comment><USER11> How about a day without work? Times two. Make it consecutive. Oh now you have a "weekend." Keep trying and one day you'll shed the addiction.

</comment><comment><USER12> My only response is this: [http://www.themarysue.com/wp- content/uploads/2012/01/tricord...](http://www.themarysue.com/wp- content/uploads/2012/01/tricorder-spock.jpg)

Sorry. -- But we've been told to "learn teaching." Where else except in the wild? User testing opportunities abound since we are developing social apps.

<comment><USER13> I don't think you responded to the right thread. And if you did, could you please expound on what you said, because it doesn't look like you groked the article

<comment><USER12> Deserved. I was trying to reach, perhaps intuitive or anticipate what is echoed in:

"One thing I like to do is take a bit of my time each week and sit down with a person who has never used my product."

What does "a day without coding" entail? Can one actually go without coding? Sure, it is one of _those_ philosophical questions. I am sure most developers code under a social routine as well. Does a "day without coding" involve changing that routine? Can one's mind compartmentalize one's projects so dynamically? What happens when an impromptu conversation turns into a user test?

But deserved. My thoughts were not quite so lucid for that post.

<comment><USER14> losethos? Is that you man?

<comment><USER12> Not so.</comment></comment></comment></comment></comment>


CPU feature flags and their meanings - <AUTHOR> http://blog.incase.de/index.php/cpu-feature-flags-and-their-meanings/ Not quite Black Viper, but a start. <comment><USER2> Cool!</comment>


Create-react-app is great but it lacks something: Redux and its configurations - <AUTHOR> https://github.com/delvallejonatan/generator-create-redux-app <comment><USER2> It's interesting you should bring this up. I'm a Redux maintainer, and I recently opened up an issue for discussion of possible useful "official" libraries or tooling that could be built on top of Redux: [https://github.com/reactjs/redux/issues/2295](https://github.com/reactjs/redux/issues/2295) .

A basic option might be a small library that simply creates a pre-configured store for you, and possibly also includes some common useful utilities (redux- thunk, reselect, redux-actions, etc). At a higher level, Dan Abramov suggested that he would like to see something that has data fetching, normalization, and code splitting built in.

Another approach would be something that sits on top of Create-React-App, kind of like what you've built here. Your tool looks interesting, although it looks considerably more opinionated in terms of React-related libraries than something we might want to dub as an "official" Redux tool.

I'd love to have you join the discussion in that issue and help us come up with ideas for ways to improve Redux and the ecosystem!

<comment><AUTHOR> I think Redux need an starter like create-react-app. Something official following the best practices, something that covers not only the world of React but also implements Redux and all the libraries necessary to make a real world application. You could have the options of including different libraries (redux-thunk, reselect, redux-actions, etc.) and it would be the devloper decision whether to include these libraries in the project or not. Yeoman offers this solution by asking before installing the dependencies.

</comment></comment><comment><USER3> Thank god it doesn't contain Redux, entirely optional and entirely complex.

Just recently someone was telling me about how hard ReactJs was to learn and from what I could glean, at least part of the learning challenge was because he felt he had to use Redux because many people perceive react and redux to go hand in hand.

<comment><USER4> That has to do with people used to frameworks and coming to React expecting that. I personally had the same issue.

If you are used to framework based development (Angular, Vue, Backbone, etc) you are not used to making decisions for yourself and to chose when to use what. Don't get me wrong, opinionated frameworks are good and fill a gap.

But you have to know that when you are developing using libraries you make those decisions yourself and thus you have to think a bit more when you chose something and why.

Redux is just one way to handle state in React apps. Might be the most used one but by any means it is the only one or the silver bullet.

</comment></comment><comment><USER5> Why not custom scripts via `--scripts-version`? How do you keep things up-to- date like create-react-app does?

<comment><AUTHOR> To keep up-to-date with create-react-app just upgrade the react-scripts dependencies. In the case of the Yeoman create-redux-app generator npm install -g generator-create-redux-app</comment></comment>


What a collapsing empire looks like - <AUTHOR> http://www.salon.com/news/opinion/glenn_greenwald/2010/08/06/collapse/

<comment><USER2> Nonsense; this is local and state governments that spent like drunken sailors during the boom now having to cut back, and doing a poor job of it. They made stupid choices in years past, like not paying down debts, lavish pension terms, lots of staff, etc. Now they don't want to cut those, and in some cases can't. So they're making panicky choices.

<comment><USER3> True, and the trend of questionable spending at all levels of government will likely continue as long as lobbyists are able to pay politicians to make these choices.

<comment><USER4> Well if the system of politics doesn't bubble those of highest integrity and uncompromising, "un-bribable" characters to the top, is that the "lobbyists" fault or isn't the system at least partially flawed in itself?

<comment><USER5> The system ain't great, but it doesn't excuse the lobbyists.

</comment></comment></comment></comment><comment><USER6> I honestly don't get it. State governments are floundering trying to cover their expenses. It seems like people need to make a choice: do we want these public services or not? If so: RAISE TAXES. God forbid we actually pay for the services we want.

<comment><USER7> A lot of that floundering is all about their big losses...Wall St, over- resourcing for the housing bubble, budgeting based on bubble math, widespread corruption and backroom dealing, oh, and there's that huge army fighting a couple big wars with a budget larger than the military of rest of the world combined.

</comment></comment><comment><USER8> He paints a picture of local/state governments declining and the federal government ascending. This is, in fact, the birth of an empire.

<comment><USER7> Only if it's sustainable. Corruption on the scale here is a known destabilizer of empires.

</comment></comment><comment><USER9> What's sad is that the US could really afford these things. It's just a matter of seriously misplaced priorities.

</comment><comment><USER10> This is what deflation looks like - very bad for any person, business, or government in debt. Quantity and velocity of money decreases, leaving less revenue to service and pay down debts, forcing cuts and austerity across the board.

This is what Bernanke is trying desperately to prevent, even at the cost of devaluing the currency by overprinting. Whether it will succeed is arguable, depending on whether the idea of Diminishing Marginal Productivity of Debt is accurate and applicable:

[http://market-ticker.org/archives/2130-On-Deficits-And- Debt-...](http://market-ticker.org/archives/2130-On-Deficits-And-Debt- Financed-Government.html)

</comment><comment><USER11> They missed a big one:

> Salaries and benefits — for identical jobs — are 30 percent to 40 percent > higher in the federal government than in the private sector. Claims that > this dramatic discrepancy in compensation is warranted because of government > workers' high skills are unjustified, as this study shows. Equally > unjustified is the fact that federal workers can rarely be fired, no matter > how poor their job performance. Congress should align federal salaries and > benefits with market rates—a simple, and fair, move that could save > taxpayers nearly $47 billion in 2011.

<comment><USER12> The original article is about budget problems at state and local levels, so salaries of federal employees aren't really relevant. Aside: the Heritage study gives a premium of 22% when controlling for education level; the authors have not controlled for experience level and have no way of controlling for intangible skill differences which might legitimize the discrepancy.

State and local employees make less then private sector employees (on average) when controlling for education, experience, and so on[1]. This is not to say that each and every municipality has been managing its budgets well; clearly many haven't, and outlying salaries seem to be part the problem[2] in specific situations.

[1] [http://www.slge.org/vertical/Sites/%7bA260E1DF-5AEE-459D-84C...](http://www.slge.org/vertical/Sites/%7bA260E1DF-5AEE-459D-84C4-876EFE1E4032%7d/uploads/%7b03E820E8-F0F9-472F-98E2-F0AE1166D116%7d.PDF)

[2] [http://www.bloomberg.com/news/2010-07-20/california- official...](http://www.bloomberg.com/news/2010-07-20/california- official-s-800-000-salary-in-city-of-38-000-triggers-protests.html)

<comment><USER11> Good comment. I just did a quick google for the government employee premium - I was thinking specifically about California since that's the state economy I know most about. Their spending on salaries, benefits, and pensions was crazy. Lots of good analysis about California's problems - Heritage wasn't actually the link I was looking for, I saw a different specific analysis but that one came up in Google first and was close enough to give a general idea.

Edit: Also, the article mixes federal and state spending. Their examples of high spending they think are wasteful are all federal - bank bailouts, assuming private debt like General Motors, and wars are all federal spending.

<comment><USER12> For some reason I don't see discussion of federal spending in the Salon article or the cited NYTimes article, except for a few offhand comments in the former which seem suggestive, not substantive (e.g. rumors about what the Deficit Commission may propose 4 months from now). Why am I missing them?

I agree about California; there seems to be plenty of evidence of exceedingly high salaries and pensions. Administrators might reasonably claim that they raised comp in order to hire top talent (for example at the UCs) and that they were successful in doing so. But they ratcheted up way past levels that could be sustained in a downturn, and at this point it seems short-sighted to the point of crazy.

</comment></comment></comment></comment><comment><USER13> Salaries and benefits — for identical jobs — are up to 5-10 times higher than the developing world... even adjusting for purchasing power parity and the cost of living.. this is too large a difference... and is becoming increasingly unsustainable.. leading to all kinds of job losses. maybe just a little bit of lifestyle downgrade in the developed world is the need of the hour

<comment><USER5> Just because others are worse does not mean we should follow their example.</comment></comment>


Blekko Bans 1.1 Million Spammy Domains Via New Algorithm - <AUTHOR> http://techcrunch.com/2011/03/09/blekko-bans-1-1-million-spammy-domains-via-new-algorithm/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+Techcrunch+%28TechCrunch%29&utm_content=Google+Reader <comment><USER2> I believe it's more of a PR stunt. Few weeks ago they banned 20 big sites which they considered spam like ehow.com and experts-exchange.com. Now I do agree that these sites do not have top notch content, but I am able to find my answers on these sites on frequent basis.

</comment><comment><USER3> Hmmm. I notice that our site is now not on Blekko (an absolutely zero-spam zero-ads tool). Thanks, Blekko; really winning me over.

</comment><comment><USER4> I think it's great that they're doing something so obviously common sense. If anything undoes Google it will be their dogmatic approach. Blekko can exploit that.

<comment><USER2> They should publish the list of blocked domains and let people decide whether banned sites are really spamy.

<comment><USER5> I believe it's here: <http://blekko.com/ws/+/topspam>

Although that includes some "normal" sites too that simply prevent crawling.

<comment><USER6> It still ends up including a lot of legitimate sites I recognize for crazy reasons. The main DNSSEC site, dnssec.net, and he security blog dshield.org are both apparently "mfa" ("made for adsense"), the musician deadmau5.com is "spam", and boonex.com, the author of the Dolphin CMS, is a "malware-domain".

With that kind of hit rate, I have to wonder how many of the 1.1M domains they banned were errors. :/

</comment></comment></comment></comment><comment><USER7> Search is so broken. The web was a better place 5 years ago, before Google started to lose to the seos and spammers.

<comment><USER8> I wish you could see all the queries you made and their results 5 years ago, try them again and see if the results got better or worse. My bet is on better.

</comment></comment><comment><USER9> Having just visted TC for the first time in a while - is commenting only possible via facebook now?

</comment><comment><USER10> devcomments.com and mahalo.com are still there, wonder which spammy domains got blocked.

</comment><comment><USER11> I like what they are doing in theory - it makes a lot of sense, but Blekko has a LOT of issues... like surfacing a domain that we got rid of 7 months ago, and showing sites that have nothing to do with the intended search (apart from a similar domain name).

Details: <http://feefighters.com/blog/?p=4554>

<comment><USER12> This exact same comment and link appears on the TechCrunch post. I'll attribute it to bad form instead of blogspam.</comment></comment>


Wikileaks.org users at risk due to a Web vulnerability - <AUTHOR>

We have been made aware of a potential security risk with open source software Wikileaks is utilizing which uses a flash library to display PDF files. Two vulnerabilities XSS and content spoofing can be used by malicious users. Whether to affect the privacy of users of wikileaks. eg: Using Flash components specifically to decloack behind Tor network users OR link to external content to discredit Wikileaks, something Wikileaks should avoid given the nature of the content published on Wikileaks servers. Given the fact that most browsers use plugins to enable the reading of PDF's, we strongly urge Wikileaks to link directly to PDF files instead of using third party software that could put users at risk<p>http://www.wikileaks-forum.com/security-support/608/-flexpaper-pdf-viewer-used-on-wikileaks-org-presents-security-risk-for-users/32700/msg66862#msg66862 <comment><USER2> Possible solution: They could use pdf.js and/or mirror the files on [https://pdf.yt](https://pdf.yt) instead.</comment>


Ask HN: Does it help to have dedicated domain for non-web apps? - <AUTHOR>

Let say currently have url for few Mac OS X desktop and iPhone apps:
http://manysoftware.com/twitclient/ http://manysoftware.com/buttockbook/ ::
Will I get more traffics and exposure to have additional dedicated domains for each such as http://twitclient.com/, http://buttockbook.com, etc? Each of these domain will host the same content as the main site. <comment><USER2> Yes, people naturally like simplicity. If you have a small enough product portfolio, it is a good idea to have a domain that points directly to that product and market that domain. It can forward to your main domain, but have a url to a targeted brochure about that product on your main site is a good way to provide clear, simple and relevant information. For example if you go to www.mac.com it forwards you directly to apples landing page for Macintosh. www.iphone.com right to the iphone page. Now that does not immediately equate to more traffic, you still have to market your site to get people to look.</comment>


The Poison of Arrogance (Google and Navx) - <AUTHOR> http://www.mondaynote.com/2010/07/04/the-poison-of-arrogance/#more-2910

<comment><AUTHOR> <snip> Navx is a €1m a year French company whose business is speed radar location databases. In France, it is illegal to sell or use selling radar detectors, devices that pick the microwave or laser radiation emitted by speed guns and automated cameras. But providing speed trap location data is lawful. ... To sell its product, Navx relies massively on Google AdWords: the company buys keywords that guarantee a high ranking in search results associated to terms like "avertisseur radar" (radar warning). </snip></comment>


Australian Gun amnesty: Rocket launcher, automatic rifles among 57K firearms - <AUTHOR> http://www.abc.net.au/news/2018-03-01/gun-amnesty-sees-57,000-firearms-handed-in-across-country/9495440 <comment><USER2> Actual title: "Gun amnesty: Rocket launcher, automatic rifles among 57,000 firearms handed in"

which itself is clickbaity, given that only 18,000 were actually "handed in" for good, with the other 39,000 going right back out either to their existing owners or back into the market.</comment>


The mathematics of team productivity - <AUTHOR> http://plusbryan.com/the-mathematics-of-team-productivity <comment><USER2> One of the best ways I have found to avoid the dividers is to give them a homework assignment at the end of their first on-site interview. A development project (like implementing a todo list with some special twist) and then coming back in and having some of the current developers peer review their code. The red flags to watch for:

1) reaction when given the homework assignment. Is there enthusiastic energy in their response or do they react with fear, uncertainty, doubt, or do they turn up their nose like the challenge is beneath them? If any but the first reaction, then dive in deeper with some targeted questions based on your observations. Sometimes they're still a good candidate but have been beaten down by prior work places, so you have to judge if their potential outweighs risk of a negative hire.

2) general disposition during code review: During 2nd onsite interview, they are there to meet and greet the larger development team and to defend their project challenge to a select few on the team. I let the developers welcome them and discuss the review process and help them settle in before going into the code review as this gives them a chance to relax and hopefully also realize "this is how its done here" -- In this session, one of two things generally happen. The candidate either shines and enjoys the whole review process and takes in the advice and critiques and willingly and quickly adapts to the feedback coming through, or he/she gets very defensive and closed- minded and shows little reception to what the team is saying.</comment>


Reflections Upon a SWATting - <AUTHOR> https://medium.com/@lopp/reflections-upon-a-swatting-a45c0209135f <comment><USER2> > While I certainly blame the attacker for the actions they took, my root > cause analysis places the blame squarely upon law enforcement for creating > an exploitable vulnerability. The militarization of police combined with > nonexistent authentication creates a great environment for SWATting.

People (like Lopp, according to his own tweet embedded in the article) own guns in the US and this is legal. Occasionally guns get used in some kind of hostage taking, robbery, murder, etc. I really don't think the blame lies with the police because they have to be equipped to handle those types of situations and that they (quite rightly) should assume every incident is real until proven otherwise.</comment>


100% winrate trading strategy open sourced? - <AUTHOR> https://www.tradingview.com/script/XnvfXLPF-NoNonsense-Forex-high-timeframe-trading-absurd-NON-REPAINTING/ <comment><USER2> > I'm showing it as an example of OVERFITTING. ... if you change any of the > many parameters ... they will turn into disaster

Come on, there's nothing to be seen here. Hyperparameters were handpicked to result in 100% profit on a certain timeframe.

And the title is misleading.

</comment><comment><USER3> Devising a set of parameters that backtests 100% means nothing - there are an infinite number of parameters and models (or more accurately, algorithms) that can backtest any data set like this 100%.

In that sense, the math and "indicators" are just an obfuscated, custom-fit version of another algorithm that backtests 100% - if price[now] > price[now+1] -> sell else -> buy.

Rather than looking up the prices via array in the data, clearly "cheating", a set of parameters is hunted down that encodes that relationship in a number space. It doesn't mean anything more than the meme: 79 beers - your age + 40 dollars = the year you were born (which backtests perfectly as long as you were born after 1900).

That said, by all means, keep running the algorithm on new data every day and see how long it stays perfect. I'd be interested in the results.

</comment><comment><USER4> I just did a quick dive into forex trading online to see what it would take to get this setup and... is it just me or are the websites and companies that run in this space the sketchiest things ever? I definitely do not trust any of these sites with the minimum deposits they are asking for.

<comment><AUTHOR> Just wait until somebody offers you "signals"... hahaha

</comment></comment><comment><AUTHOR> Hmmm, so I took this source code, compiled and it is still 100%.

I mean - the strat was published 8th of November, and you could say it was overfitted. But it continues to run. Since 8th of November it closed only 1 trade, but also $500+ profit. (second is still going, but currently profitable).

</comment><comment><USER5> TL;DR Title is misleading clickbait but the semi-interesting part is:

> Backtesting results [of the backtesting strategy referenced] look absurd: > 100% profitable. But if you change any of the many parameters in the > Settings popup, they will turn into disaster. It means, the rules of this > strategy are very fragile. Don't trade this! Remember about backtesting rule > #1: past results do not guarantee success in the future.

<comment><USER6> I've always wondered about this. Of course back-testing a specific timeframe doesn't mean anything. But if I backtest a strategy on multiple timeframes in a sliding window fashion and am always profitable - doesn't that mean anything? Would you still say that past results do not guarantee success in the future?

<comment><USER3> It still just means you're finding parameters that match some subset of the relationships present in the data as a whole.

All sliding the window does is discover the parameters that work for the whole data set in chunks - it is an artificial distinction. It still regresses to: you've found some number space generated by some function that matches some percentage of the numerical relationships (correlations) present in the data.

It's circular reasoning because during creating the parameters you're testing it on the "future" data. It only "guarantees" success in the "future" because you discarded all the parameters that didn't work in the "future". No different from writing a model that uses the S&P 500 price "parameters" between 250 and 1000 and back-testing it on data from 1950-1996.

The only way to prove your algorithm's robustness is to generate random data and test it on that. Once you've tested against every one of the infinite possible realities of a single time window, then you can rightly assert that past results have guaranteed success in the future. Hint: it's impossible, but the random data testing is actually the correct technique to test algorithms at scale.

Back-testing on historical data is like a footnote compared to the thesis simulation can generate - the only value it contains is correlating relationships between market data and external variables not present in the numbers. Back-testing to tune an algorithm based purely on the numbers in the data is just an exercise in quantified hind-sight bias.

<comment><AUTHOR> > The only way to prove your algorithm's robustness is to generate random data > and test it on that.

I would never to that. This algorithm appears to have worked well on EURUSD daily timeframe candlesticks data. It would be ridiculous to assume that it can work well on a random set of data, like global average temperatures daily or rate of births worldwide. Or even prices of oil or other currency pair.

<comment><USER3> "Random data" didn't mean a random data set from a different domain. It meant random data from the same domain - simulated price/volume data within a reasonable range. If it can't work well on that, then it isn't a trading algorithm, it is a glorified fit curve.

<comment><USER7> > It meant random data from the same domain - simulated price/volume data > within a reasonable range

How do you know what is a reasonable range _without_ hypothesis on the price distribution ?

Where does these hypothesis comes from ? historical data ?

So.. is that really valid ?

<comment><USER3> yes. You know the lower bound on price is 0, and the upper bound of infinity is probably of no practical value, so you can pick something like 10 or 100x max all-time. Volume is the same, 0 to infinity, but again you can pick a distribution that is much (10-100x) wider than the real one. The wider the better, as it will better uncover tail risks and payoffs for highly unusual or atypical events (see Taleb, Black Swan, etc.)

I'm not making this up - this is how model testing is actually done, in multiple domains. Simulation is a reason banks, HFTs, hedge funds, etc. use massive compute infrastructure - doing it the right way, with many millions of plausible data sets, requires orders of magnitude more computing resources than back-testing on one data set that just happens to represent one way things could have played out (i.e. reality).

Thinking that one historical data-set is somehow special (in itself, without context) is largely a delusion. In fact you can generate near perfect historically accurate price charts just using a random walk algorithm seeded with an opening price.</comment></comment></comment></comment></comment></comment></comment>


The Pragmatic Bookshelf 40% Black Friday Sale - <AUTHOR> http://www.pragprog.com/ <comment><USER2> I highly recommend Pragmatic Thinking & Learning - it probably gets overlooked amongst all the other straightforward howto books but it's the one that's had the biggest impact on me personally.

[http://www.pragprog.com/titles/ahptl/pragmatic-thinking- and-...](http://www.pragprog.com/titles/ahptl/pragmatic-thinking-and-learning)

It's not yet another GTD productivity clone either, it has some interesting research into both the brain, as well as an explanation of how the tech industry is could learn from the educational revolution in the 70's in nursing and health care (of all places!)

<comment><USER3> Got this book in last year's sale. Still need to go back and finish it, but it's an amazing book from the ~half I read.

Ended up picking up Driving Technical Change because it sounds useful in general, not JUST from a technical perspective.

<comment><USER2> Oh this is _really_ cool, I never heard of Driving Technical Change. I could definitely use the tips because I've been instigating some technical changes at work recently: svn to git, php to rails, big product features to independent small focused apps, etc.

EDIT: I wish we could start an HN book club, but I'm not sure how well the discussions would work virtually. I've attended and moderated a local UX design book club and gotten a lot out of it, so maybe a local HN chapter might work.

Also: HN won't let me add a reply to the bottom of this thread, maybe it's one of pg's new features to avoid flame wars?

<comment><USER3> It just came out a week or two ago, so it's brand new. I haven't started in on it yet (too many other things going on) but the table of contents screamed "Understand how to get past people's misconceptions/preconceived notions" which, I dunno about anyone else, but I could use all the time.

</comment></comment></comment></comment><comment><USER4> You need to use the coupon code "turkey" at checkout. The discount is not automatic.

</comment><comment><USER5> New paper copies of the books I looked at ("Seven languages in seven weeks", "Pragmatic Guide to Git") are about 40% off list at Amazon all the time.

<comment><USER6> those are the two books I bought :)

</comment></comment><comment><USER7> I bought "Seven languages in seven weeks", "Behind closed doors" and "SQL Anti-patterns" this morning. (CET)

The e-books were available less than 5 minutes after ordering and everything went very smooth.

</comment><comment><USER8> 1 order from Amazon for "Hello, Android" placed Oct. 29th, expected arrival after Dec. 25th with the possibility of a Feb. 22nd delivery date!? But it's in stock over at Amazon... Oh wait, looks like I'll be getting it directly from the source. Go, go, gadget 'turkey.' Thanks for letting me know about this woan. Now I can get it for the same price and don't need to wait a month or more.

</comment><comment><USER9> Just bought the ebook of Seven Languages in Seven Weeks. I liked Bruce Tate's talk on it at Lone Star Ruby Conf; I was going to wait to buy it until I actually had time to read it, but I figure it'll never be cheaper than right now. Looks like a really good book.

</comment><comment><USER10> Got 6 (e)books today for <$100, some ones that I probably would not have gone for without the sale but that will likely be helpful to me. A win-win, I think.

</comment><comment><USER11> I bought Hello Android, TDD screencast series & The RSpec Book. Amazing bargain!

</comment><comment><USER12> Just picked up a few myself, thanks for the reminder.</comment>


Ori File System - <AUTHOR> http://ori.scs.stanford.edu/# <comment><USER3> To the authors: please add immediately accessible documentation, best in form of a 'Quick Start' document. Also please add one page to your website that you call 'Features' where you describe what it can do / can not do and add another page to your site that you call 'Documentation' where you put the USER DOCUMENTATION. No, nobody wants to read a paper to get some sync software up and running. THANKS!

</comment><comment><USER4> I promise I'm not being dismissive.

My question is:

 _Ori is a distributed file system built for offline operation and empowers the user with control over synchronization operations and conflict resolution. We provide history through light weight snapshots and allow users to verify the history has not been tampered with. Through the use of replication instances can be resilient and recover damaged data from other nodes._

Does a user actually want to do any of these things? Not a techie user, but a user. Someone who cares about their photos, for example.

One big use case, which I often run into, is that Dropbox is very valuable because it serves your files through a website. Yes, that means Dropbox and governments have access to that data. On the other hand, it's fine for Dropbox and governments to access my "chatlog with my ISP where I complain about a late fee and ask for a refund" that I saved to Dropbox but need to pull up on my laptop which doesn't have Dropbox installed. That type of thing is where Dropbox really shines, so I'm not sure I'd want to put my docs into a system which doesn't have a web interface.

Those kinds of "casual documents" are extremely common. I'd say most of my stuff in Dropbox isn't actually sensitive, whereas a small percentage is highly sensitive. It'd be great to store the highly sensitive into a filesystem like this, since I could control it directly, but that involves quite a lot of effort to set Ori up and to understand it. And it's not entirely clear that it's more secure than, say, encrypting my Dropbox files directly.

In summary, what precisely is the value add that Ori brings to the user? I'm trying hard to see it, and I want to believe there is one.

<comment><USER5> I think there is definitely a growing segment of people who do not want to contribute to the growing surveillance of their lives, but nevertheless do want to have a way to share their data and details with whoever they want, with trust, at a personal level.

I know a few families, for example, who are now using their own social-media apps built by family members, and for which there is no outside access - <USER2> they have their own network, trust system, shared media and data, and so on.

It is _completely_ within their control.

So there are people out there for whom Ori and its peer technologies are very important. Not everybody wants to just genuflect in front of the ultra- corporate ruler(s). Its quite possible to continue using computers unhindered by third parties; tools like Ori assist that - technologically as well as culturally. Get all your friends on their own p2p networks.

<comment><USER6> On the other hand, Synology NASes with new DSM already offer a better alternative - web access to data, sync with other computers and other services while you still own your data. In that case Ori doesn't bring all that much to the table :)

<comment><USER7> Synology NASes have had a number of security vulnerabilites and privacy breaches over the last several years.

<comment><USER6> Yes, and they were rather quickly patched. I'm not really sure what are you trying to say... to avoid security vulnerabilities, just upload all your data to a foreign datacenter?

<comment><USER8> check out the synology employee

</comment></comment></comment></comment></comment></comment><comment><USER9> My company has three offices. We have about 200GB of shared storage. We often need to access and write files that are 10-20MB in size. Currently we have a centralized file server at the main office and a VPN. Using the file server at the main office is a pleasure, using it from the other two offices is slow. I am looking for a stable distributed filesystem, so that I can have a full copy of the data on a server at each of the three locations. I wish to share between each server and it's local clients via both NFS and Samba. Clients should be able to read and write to their local server, and the three servers should collaborate to keep all their data in sync. Can Ori offer this? Something else?

<comment><USER10> Depending on the exclusivity/locking requirements, and the amount of changes, you might be better off with complete replication among offices, such as DropBox (if you trust them) / SparkleShare (if you want to host yourself - sync is less efficient though), or simply rsync scripts going back and forth.

A key for convenience, which DropBox delivers, is to fetch the data before you need it. 200GB is not that much in the grand scheme of things today - if you only have 1GB/day of changing data, it could be viable.

<comment><USER9> I set up syncthing, it's syncing now. I think this software will do exactly what I want. It's a standalone binary and runs as a standard user space app, keeping data synchronized between all the systems without the need to mount a new filesystem or do any advanced configuration.

</comment></comment></comment><comment><USER11> I have not looked into this much yet, but I think comparing it to Dropbox etc. like many are in here is silly. There is a huge amount of use cases where people work with large amounts of shared data in lan environments over nfs and such. This is very much tied to location and becomes a bit tricky to make offline, remote, conflict proof. Something like git can support distributed workflows in work groups, but it only works with light weight data and needs pretty educated users. I think programmes under appreciate how horrible it still is to work together with others using computers.

</comment><comment><USER12> I wasn't quite able to grasp what this is. Is it similar to dropbox / btsync (without the bt part) in what it provides to the user? What are the usecases? Looks cool anyways, and I love that packages are already available!

<comment><USER13> Neither dropbox nor btsync are free software afaik. I would be excited about a viable open source alternative.

<comment><USER14> [http://syncthing.net](http://syncthing.net)

<comment><USER15> If only Syncthing was as easy to use as BTSync.

</comment></comment></comment></comment><comment><USER16> Previous discussion: [https://news.ycombinator.com/item?id=7072492](https://news.ycombinator.com/item?id=7072492)

</comment><comment><USER17> I don't see any end-user documentation (only a short building section). Is this not a release, but the project's "work in progress" page?

<comment><USER5> Yeah, I would have to say that Ori has the worst documentation ever. Except, this is pretty useful:

[http://sigops.org/sosp/sosp13/papers/p151-mashtizadeh.pdf](http://sigops.org/sosp/sosp13/papers/p151-mashtizadeh.pdf)

</comment></comment><comment><USER18> Reminds me of Brad Fitzpatrick's camlistore [http://camlistore.org](http://camlistore.org)

</comment><comment><USER19> Looks kind of interesting to me. How does it compare to use a git repo as a "decentralized file store"? What is the speed of this thing.. I see it uses fuse, which generally isnt that fast. Speed probably isnt a goal, but none the less important. To make this a succes, docs should be available. Now it feels like a research project to me.

<comment><USER19> I quickly scrolled through the paper a few people mentioned earlier. About speed:An evaluation shows that as a local file system, Ori has low overhead compared to a File system in User Space (FUSE) loopback driver; as a network file system, Ori over a WAN outperforms NFS over a LAN.

Interesting. Git is mentioned as well. I guess i have to read the paper after i finished cleaning the house ;)

</comment></comment><comment><USER20> This is pretty cool stuff, but when I tried it in mid-2014 (release 0.8.1), there were stability issues with orifs, and the user interface was rather confusing. Quite possibly these issues are resolved now, as I see there have been new commits again from October onwards.

</comment><comment><USER21> Usually I want only a subset of my synchronized data on my phone. Can I set this up so all my data is synced to my nas but only some to my phone?

</comment><comment><USER22> does it work best on local networks, or is it also good when there's high latency and lower bandwidth ?

</comment><comment><USER23> Hallowed are the Ori

<comment><USER24> Came in to post this. Thank you.</comment></comment>


Please review my startup - <AUTHOR> https://www.snooze.io

<comment><AUTHOR> Repost from last week, but I accidentally posted it in the new instead of the ask thread, sorry! I'm particularly looking for feedback about how to explain the product better (aka creating a better sales pitch). Somehow I find it very hard to explain a simple product :). Now also available outside of Europe.

<comment><USER2> It is quite hard to explain! I didn't get it from the headline "heartbeat monitoring" \- I assumed it was a medical startup.

It's definitely a problem I have, particularly checking backups reliably run. Feels like it should be a feature of, say, Pingdom though.

<comment><AUTHOR> "Pingdom but reversed" crossed my mind as an option :)</comment></comment></comment>


Do - <AUTHOR> http://dcurt.is/do

<comment><USER2> Neat 'recipe for success' but what's there to discuss?

</comment><comment><USER3> Another one-liner</comment>


NetSpectre: Read Arbitrary Memory Over Network [pdf] - <AUTHOR> https://misc0110.net/web/files/netspectre.pdf <comment><USER2> The AVX side channel is neat. It relies on power management rather than cache: after 1ms of AVX2 inactivity (no 256 bit operations being performed), it goes into a power-saving mode; the next 256-bit operation pays a ~2x cycle penalty. They get 8B/min at low error rate with AVX2.

In Google Cloud, from unrelated instances, they're getting 1 byte every 8 hours (3 if the target has an AVX2 gadget). Attacks tend to get better over time, but still, that's an AES key in a few days, and it assumes one discrete target; in a real deployment, that secret might be mirrored over hundreds of instances.

<comment><USER3> It's an AES key if you know where to look. Do these style of attacks let you view the memory map or do you just pick a place? How troublesome is this, really? I'm actually curious. I never saw where you find the point in memory to point your Spectre gun.

<comment><USER4> I'm a little vague on the details, but I think there are some tricks you use to narrow it down and then go spelunking. Maybe a particular variable needs to be in a page aligned struct so you only need to find a magic value at one of N places, etc.

Like I said, I don't know the specifics, but there are methods of doing better than guessing.

</comment></comment></comment><comment><USER5> The paper seems to say that they attacked a victim program that was specifically written to include vulnerable gadgets.

Is code for this victim program available? I don't see it in the paper.

Have such gadgets been found in any real-world programs?

<comment><USER6> Checking a user provided index is valid before using it is certainly a common idiom. There are many reasons why attacking programs in the wild would be more complicated, but delaying publication until then is probably a poor option. The contribution here is not a single attack against vuln ware release 2.3.12, but a new (or expanded) attack class.

<comment><USER5> Right but didn't we already know that this hypothetical attack class exists? The possibility of remote spectre exploits like this was discussed in the original spectre paper.

It's certainly interesting to construct an example and show it working, but this isn't surprising, is it?

Just trying to understand if I've missed something here.

(The AVX side channel is certainly new and interesting, though!)

<comment><USER7> Other than the AVX side channel, the interesting thing is that it demonstrates that the remote aspect definitely works. Before, it was theorized but might have proven to never give sufficient signal. While many were confident, now we know.

Further, it shows how to do it (classifier) and gives a very good model for what bandwidth can be expected in practice. And still further, that bandwidth is entirely sufficient for attacking long lived cryptographic key material. Before, it was easy to theorize that the bandwidth would simply be too low. Now it isn't.

This is also really good because the bandwidth _is_ really low. For data larger than a key (or where you would need to scan a lot to find the data), we can be much more comfortable with infeasibility arguments by basing them on some security margin beyond these experiments. As an example, if it would take 1 <timeunit> to exfiltrate a single credit card number even if the technique got 10 times better, maybe that means it isn't a sufficient risk. Or maybe it _is_. (All depends on the time unit and the risk.) But now we can make that assessment with a real baseline instead of a guess.

<comment><USER5> Indeed, that makes sense. Thanks!

</comment></comment></comment></comment></comment><comment><USER8> This can pretty much all be laid at the feet of overly complex CPU designs and instruction sets. Looks like complexity is as evil for security in hardware as it is in software.

On the plus side part of why you see more of these kinds of attacks is that we have actually made progress on software security.

<comment><USER9> > overly complex

Speculative execution is what makes our sequential code fast by exploiting parallel execution pipelines that would otherwise sit idle.

Avoiding this would increase complexity somewhere else, e.g. compilers would have to become even more clever or programmers would have to work harder to reduce the branches in their code. Sprinkling code with annotations to prevent speculative execution around sensitive data is of course just another way complexity does go up to let us keep the performance gains of speculation.

<comment><USER8> Complex compilers seem better than complex chips because the former is software and can be fixed.

I'm wondering these days if Intel was onto something with EPIC/Itanium and just failed in the execution.

<comment><USER10> They were definitely onto something. They made something competitive performance-wise that wasn't vulnerable to all of these speculative execution vulnerabilities.

Itanium's slowness is generally very exaggerated (at least in part because the first Itanium had a rather slow memory subsystem, and the performance kind of sucked as a result). Circa 2008 or so the fastest database servers available were Itanium. Unfortunately, it emulated x86 extremely slowly and amd64 ran x86 very quickly, so AMD kinda ate Intel's lunch.

<comment><USER8> If I were at Intel management I might explore with engineering resurrecting the Itanium (rebranded and modernized of course). Today with so much open source there is less instruction set lock in, and with all these vulnerabilities you might be able to market it as a more secure architecture. In that case you might only need to equal x64 performance.

</comment></comment></comment></comment></comment><comment><USER11> I'd be curious the setup the researchers used. The paper doesn't release the code or stack. It feels contrived but I'd be interested to be able to replicate. Trying in real, production environments, at least so far, has not been able to replicate any bit transfer rate. Has anyone else been able to reproduce? If so, can you share the specifics of your test?

</comment><comment><USER12> Cool news!

Does anyone know of a good writeup on the original vulnerability that's a little less technical? Like a lot of people on HN I came into programming via systems administration so I don't have a lot of low level knowledge.

</comment><comment><USER13> Spectre just became a much bigger problem.

<comment><USER14> not really... this is only a vulnerability in so much as specific gadgets were intentionally placed in code. it's more of a danger for intentional data exfiltration covertly, not an issue of attacking random servers like ssh or web servers to get keys. show me a vulnerable ssh or web server and i'll be worried, otherwise, this is just hype about a new class of theoretical attack that has no known actual real world targets.

<comment><USER14> to further elaborate, it would take 85 days of 4gbps network link being 100% saturated to leak a 256 bit key, assuming you know the memory locations, assuming no ASLR, assuming the key doesn't move or change, and assuming a vulnerable spectre gadget running on the system, which means you already have RCE in the first place. this class of attack is easily mitigated, and has no real world implications. if you don't notice a 4gbps link being fully saturated for months at a time, you have bigger problems. otherwise, if you don't reboot a server or restart services within 85 days, and if you don't use ASLR, you have bigger problems. if you let someone run spectre code on your system, you have bigger problems.

this class of attack is theoretical, and all the hype is unsubstantiated. clearly y'all haven't read the paper. people never read past the headlines any more...

you don't even have to take my word for it, READ THE PAPER:

> As NetSpectre is a network-based attack, it cannot only be preventedby > mitigating Spectre but also through countermeasures onthe network layer. A > trivial NetSpectre attack can easily be detectedby a DDoS protection, as > multiple thousand identical packets aresent from the same source. However, > an attacker can choose anytrade-off between packets per second and leaked > bits per second.Thus, the speed at which bits are leaked can simply be > reducedbelow the threshold that the DDoS monitoring can detect. This istrue > for any monitoring which tries to detect ongoing attacks, e.g., intrusion > detection systems. Although the attack is theoretically not prevented, at > some point the attack becomes infeasible, as the time required to leak a bit > increases drastically. Another method to mitigate NetSpectre is to add > artificial noise to the network latency. As the number of measurements > depends on the variance in network latency, additional noise requires an > attacker to perform more measurements. Thus, if the variance in network > latency is high enough, NetSpectre attacks become infeasible due to the > large number of measurements required.</comment></comment></comment>


'Time telescope' could boost fibre-optic communication  - <AUTHOR> http://www.newscientist.com/article/dn17867-time-telescope-could-boost-fibreoptic-communication.html?DCMP=OTC-rss&nsref=online-news

<comment><AUTHOR> Here is the publication

[http://www.nature.com/nphoton/journal/v3/n10/abs/nphoton.200...](http://www.nature.com/nphoton/journal/v3/n10/abs/nphoton.2009.169.html)

</comment><comment><USER2> Posted elsewhere, but sometimes good posts sink for no reason here...and this story deserves some love. 270Gbps is nothing to sneeze at!

Nature link is an $18 paywall, but the Cornell Photonics group put all their papers up as pdf so I'm sure this one will jin them soon - <http://nanophotonics.ece.cornell.edu/publications.html> \- there's a nice mix of blue-sky and coming-soon stuff.

</comment><comment><USER3> <http://news.ycombinator.com/item?id=852219>

<http://news.ycombinator.com/item?id=852231>

<http://news.ycombinator.com/item?id=849323></comment>


Dribbble - Teams - <AUTHOR> http://dribbble.com/teams <comment><USER2> Very cool. The page to sign up is here:

[http://dribbble.com/teams/soon](http://dribbble.com/teams/soon)</comment>


Parasite in cat poop linked to higher likelihood of entrepreneurial behavior - <AUTHOR> https://www.businessinsider.de/parasite-in-cat-poop-linked-to-entrepreneurial-behavior-2018-7 <comment><USER2> I've been eating cat poop every day for the past month, and I have not made any more money yet. Am I not eating enough?</comment>


Apple Seeks Import Ban on Samsung Smartphones - <AUTHOR> http://www.macobserver.com/tmo/article/apple_seeks_import_ban_on_samsung_smartphones/ <comment><USER2> These kinds of lawsuits don't make it fun for the consumer. Weren't patents supposed to be good for society?

<comment><USER3> In the US, yes, they were: "To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries." [https://secure.wikimedia.org/wikipedia/en/wiki/Copyright_Cla...](https://secure.wikimedia.org/wikipedia/en/wiki/Copyright_Clause)

</comment></comment><comment><USER4> insecure much?</comment>


VPS providers to shut down on Monday, giving customers two days - <AUTHOR> https://www.zdnet.com/article/20-vps-providers-to-shut-down-on-monday-giving-customers-two-days-to-save-their-data/ <comment><USER2> It's fairly simple to get your money back (in the US at least). Just call your CC company and issue a chargeback. They will not argue and within a few minutes you will have a credit while they investigate. This works with companies who declare bankruptcy or just disappear. I've used it several times, including at a dog care facility which closed with no warning after I'd prepaid for some vacation care for our dog.

Forgot to note: This obviously assumes you paid with a CC and not a check or paypal or BTC. It is in my opinion one of the major benefits of paying for things with a CC.

</comment><comment> ga-vu 20 VPS providers shut down this weekend, which brings the total to 68 in the past four months.

Pretty big deadpooling scam.</comment>


RethinkDB 2.1.5 performance and scalability - <AUTHOR> http://rethinkdb.com/blog/rethinkdb-performance-report/?hn <comment><USER2> We use RethinkDB for our home grown monitoring system; it's incredible. We have several hundred clients connected, inserting monitoring data and doing some pretty complex queries. In the ~2 years we've been using RethinkDB, we have never experienced a failure.

If I could go back in time, I would use RethinkDB for our actual product.

<comment><USER3> Has the live query stuff performed well? i.e. subscribing to some arbitrary db query for new records?

</comment></comment><comment><USER4> This is probably my favorite database to work with currently. Real time, relational document storage. Best of three worlds.

<comment><USER5> Relational documents? That sounds like graphs but Rethink is not a graph database (compared to Neo4j, GUN, Orient, Arango, etc).

Do you have a link to explain what you mean?

<comment><USER6> What would you say is the distinguishing feature of whether something "is a graph database"?

To put it another way, what do the databases you listed have in common with each other that they don't have in common with other NoSQL databases, besides marketing?

<comment><USER7> A graph database exposes an object model that fits graph terminology: nodes and edges. They (hopefully) are optimized for graph-traversal operations like hopping along a series of edges, which would be painful in a relational model.

In this situation, NoSQL is the marketing term, while a graph database is a clear concept with corresponding performance and capability expectations.

<comment><USER6> I'm not asking you to explain to me what a graph is.

I've found that it's easier and faster to import and traverse edges in SQLite or PostgreSQL than in some of the systems you listed. I haven't tried RethinkDB but it sounds promising. You use words like "hopefully" and "performance and capability expectations", but distinguishing databases based on their hopes and expectations is not at all a clear concept.

The main difference seems to be whether you call things "nodes and edges" or "documents and references" or "rows and joins" in the documentation.

(edit: removed some negativity, and I'm aware some remains)

<comment><USER8> The most common and relevant difference is that a graph database has a storage engine that is optimized for graph traversal. For example, in a RDBMS, another row is referenced via a foreign key which involves a lookup to an indexed column, while in a graph database, a node is often referenced by its storage location. This makes graph traversals much cheaper, and is also something that an RDBMS is unable to optimise for because of conflicts with the relational model.

Similarly, the query language is optimised for graph traversal types of queries, in a way that would not be possible in an RDBMS due to the relational model constraints, and also because some of the query operations would be extremely inefficient in an RDBMS storage engine.

> That sounds like graphs but Rethink is not a graph database (compared to > Neo4j, GUN, Orient, Arango, etc).

With regards to the listed databases, some are, but the rest are not (and do not claim to be) graph databases.

Note: It's different people replying to you.

<comment><USER6> FWIW, I should mention that I _have_ tried one DB that seems to qualify as a graph database, in that it actually does seem to import and traverse edges efficiently, which is Blazegraph. You tend to have to search past several other things calling themselves graph DBs to find that one.

(But I'm a bit afraid of using it. Any armchair lawyers want to tell me if code that uses a GPL database has to be GPLed itself?)

<comment><USER9> Don't worry about the GPL part, e.g. see MySQL as a GPL database in wide use.

As long as you access blazegraph via the sparql or tinkerpop interfaces you will clearly be fine.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER10> I _really_ like using rethinkdb. Currently, I am using thinky for node as an orm which works quite well for my purposes. If anyone else works with nodeJS I would be interested to know:

* how you use rethinkdb

* what you don't use it for, and why

* good examples resources like ORMs, repos, and data models.

Some things I like/use/reference:

\- [https://github.com/drhurdle/node-rethinkdb-auth- starter](https://github.com/drhurdle/node-rethinkdb-auth-starter)

\- Yo Express, provides a nice structured MVC application with thinky and rethinkdb with gulp

\- [https://www.airpair.com/javascript/posts/using-rethinkdb- wit...](https://www.airpair.com/javascript/posts/using-rethinkdb-with- expressjs)

<comment><USER11> While thinky is great and does a ton of heavy lifting for me, I've found it a little bit confusing when needing to write more advanced queries. I would personally recommend to start learning reql + rethinkdb with the rethinkdbdash[0] driver first. It helps with managing connection pools and working with Promises but still lets you play nice with the (very good) rethinkdb docs while ramping up.

[0]: [https://github.com/neumino/rethinkdbdash](https://github.com/neumino/rethinkdbdash)

<comment><USER12> We had this experience as well. We started using Thinky for a few projects, but found that as soon as we need more complex queries it became very awkward to work within Thinky to do those.

Eventually, we discovered ReQL by itself is just great to work with (especially with rethinkdbdash). Writing your own queries also has significant atomicity benefits over Thinky.

<comment><USER4> You can mix and match your own queries with Thinky helper functions. I do it all the time with .getJoin. Do some more advanced REQL query, getJoin it into your other Thinky defined models. Thinky is great for the modeling/relationship aspect, setting up default values based on returns from anonymous js functions, ensuring indexes, and dealing with referential integrities when you want to recursively delete related documents. Managing all of that manually, while it's doable, would be a giant pain in the ass. Point is, Thinky and raw REQL work together.

<comment><USER12> It's really not that bad to manage that manually! The models we replaced with Joi validators, the relationships we weren't using anyway anymore because Thinky has some limitations to them, default values are easy in Rethink, index management just became part of normal migrations, and referential integrities aren't actually guaranteed in Thinky since it's not atomic so we found explicit chained promises to be more intuitive :)

Thinky and raw ReQL definitely work together, don't get me wrong! But as our project scaled we found 95% of our code had become raw ReQL for atomicity, performance, and relational reasons, so it just didn't make sense to use Thinky in future projects. Our original RethinkDB project still contains Thinky, but it'd be cleaner if we just made a complete switch at this point too.

To each their own though, of course!

</comment></comment></comment></comment></comment><comment><USER13> What are some counterindicated use cases for rethinkdb?

<comment><USER8> Besides multi-document transactions, I've encountered these problematic use- cases (something I discovered after scope creep of projects):

2\. When I needed "more exotic" data types (e.g. but not limited to Decimals) where you want query/analytics logic to happen on the database rather than the app.

3\. OLAP types of use cases. I really wanted collation, sort order, query optimizers, ability to "explore" the data in relational ways, and so on.

<comment><USER14> What did you use to solve these two use-cases?

<comment><USER8> Couldn't figure out a way to solve them reasonably (and within schedule) using RethinkDB, so I did a "master-slave" with the RethinkDB as the master and PostgreSQL as a slave replica. Then did all the queries and analytics on the PostgreSQL database. I think this is far from ideal in terms of server costs, but scope creep is never ideal.

I suppose using computed property indexes in RethinkDB might work as well, or generating indexes, sort order, and doing query optimisation outside of the DB, but I couldn't figure it out in time, and it also seemed way more complicated than replicating the data to PostgreSQL.

EDIT: Above is for the OLAP use cases. OLAP of some types just don't go well with document databases. For the Decimal type, I stored it as a string, and had a computed property that transformed the string to a float. The float can then be indexed and queried like a number. It was good, until all the other OLAP use-cases creeped in.

Having said that, I found that custom replicas with RethinkDB is easy because it emits data change events. Never expected that feature to be an escape hatch.

</comment></comment></comment></comment><comment><USER15> I love how the rethink team keeps improving an otherwise wonderful document database. ReQL is also super nice. :)

</comment><comment><USER16> Does anyone have real prod scale numbers - even order of magnitude concurrency would be helpful. We're obviously very wary of trying out new and young data stores.</comment>


Ask HN: Is "Trustwave" Legitimate? - <AUTHOR> A small business owner I know just got an email from trustwave.com about urgently needing to log in to their "PCI Manager" and update their "Scan Attestation". I assumed it was a phishing email at first, but I did some research and a) PCI compliance has to do with accepting credit card payments, which they do (though they're just a local shop; they don't have any custom tech around doing that), and b) trustwave seems like it may be a real company: it has a website and a Wikipedia page, and the latter has been around for ~4 years though it's also marked as "reading like an advertisement".
How do I know if this is legit? I equally don't want them to get phished and don't want them to have a problem with their PCI status. <comment><USER2> Unless the business owner already uses Trustwave, which it doesn't seem like they do, then I'm pretty sure this is a phishing email or spam. Trustwave themselves seems like a legit company. I've _heard_ of them but I don't have any first hand experience with them.</comment>


The beautiful welding on a Tesla Model X crossmember subframe part# 1048801-00-A - <AUTHOR> https://i.ebayimg.com/images/g/wLsAAOSw-2hcJZrA/s-l1600.jpg <comment><USER2> I've worked for aluminum product manufacturer New Age Industrial, Inc., and the welds on this crossmember are nowhere near the quality NAI produced.

<comment><USER3> Looks like OP missed the /s :-)</comment></comment>


Ask HN: Seattle area attorney specializing in SaaS - <AUTHOR> Hi HN, any recommendations for a Seattle area attorney to help with Terms & Conditions language for a SaaS with enterprise and other B2B customers in US, EU and elsewhere? <comment><USER2> Try the King County Bar Association Lawyer Referral Service > [http://www.kcba.org/lrs/](http://www.kcba.org/lrs/)

</comment><comment><USER3> Is there a reason this would need to be a Seattle attorney?</comment>