Philip Greenspun’s Weblog

Folks:

We’ve drafted an RDBMS versus NoSQL article for the three-day RDBMS course that we’re teaching this weekend at MIT (you’re welcome to take the class, even if you’re not an MIT student; just email me). The article is intended to support a 20-minute discussion and give students pointers should they be interested in learning more. As neither Andrew nor I are NoSQL experts, comments would be appreciated.

Thanks.

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As I was apparently the only Jew handy during a blizzard that dumped 14-18″ of snow in the Boston area, I was asked to comment on whether Sarah Palin’s video (youtube) regarding the Tucson shootings was offensive. Here’s my analysis

• 30 seconds: “our exceptional country, so vibrant with ideas” … “a light to the rest of the world”; The rest of the world doesn’t seem to be in a rush to copy our political system. Most democracies are parliamentary. Do we have better or more ideas per capita than other countries? Certainly we’ve had more per-capita wealth for implementing those ideas, but where is the evidence that we’re more creative than everyone else on the planet?
• 60 seconds: “inexcusable … evil man took lives”; is there any evidence that the killer himself wants to be excused? Certainly nobody else has come forward to say “I think what Jared Loughner did was reasonable under the circumstances”
• 1:24: “spent the last few days… praying for guidance”; if God helped out with this video, I would have hoped that He could have varied the camera angle a little (yes, I know that I’ve done some equally lame work for my helicopter stuff, but my production budget is lower than Ms. Palin’s)
• 2:40: “Obama would join me in affirming the health of our democratic process” [based on there being some turnover of seats in every election]; contrary to Ms. Palin’s statement, it is extremely difficult for an incumbent Representative to be voted out of office. Congressmen and women choose their voters by rearranging districts; voters do not choose Congressmen in most cases. If the vulnerability of incumbents is a measure of political health, as Ms. Palin suggests, we’re not in the best condition.
• 3:31: “journalists should not manufacture a blood libel”; analyzed separately below
• 6:20: “it is in the hour when our values are challenged that we must remain resolved to protect those values”; this has been a very common sentiment expressed in Supreme Court opinions, e.g., when FDR was advocating throwing out the Constitution in order to deal with perceived emergencies during the Depression and World War II. The government would say “we need to regulate all of this stuff that has nothing to do with interstate commerce because of the crisis” or “we need to intern more than 100,000 Japanese-Americans without a trial because they might be a risk”. The sentiment is almost always in the dissenting opinion, with the majority agreeing with the government that the crisis trumps whatever freedoms people had formerly thought the Constitution gave them.
• 6:30 “we had to fight the tendency to trade our freedoms for perceived security [after 9/11]”; Did we win this fight while I was waiting in the security line at Logan for my new X-ray scan?
• 6:55: “we need God’s guidance”; this seems like a bad way to deal with criminal justice or politics since people of different religions will get different guidance from God, at least to judge by what is written down in the world’s various sacred texts. A Jain, for example, would surely not hear divine voices telling him to invade another country, execute a convicted criminal, or do a lot of the other stuff that our government does.
• end of video impression: Palin’s face looks remarkably square (maybe it always looks like this? I haven’t seen any of her other videos and did not watch any TV coverage of the 2008 campaign (since I predicted Obama’s victory back on December 12, 2007))

Was Palin’s use of “blood libel” offensive to me or other Jews? Was it a reasonable analogy? Wikipedia notes that an unexplained murder in Norwich was blamed on the Jews. Palin was discussing an unexplained group of murders (probably nobody other than Jared Loughner will ever know the real reason) and how some journalists were blaming it on people who’ve made statements opposing Democratic Party initiatives.

Personal conclusion: Not offensive and perhaps the most accurate and sensible part of the video.

[Separately, I’m trying not to look at any news about this incident because it would be too sad to think about a 9-year-old girl dying, even if she were the only victim. According to some historians, Stephen Foster wrote Gentle Annie (lyrics; Marilyn Horne singing) after the death of a young girl in a carriage accident. For those of us who lack such talent, what purpose can be served by reflecting on the sad events of last weekend?]

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Folks: This weekend I’m teaching a class at MIT on RDBMS programming. Sadly I forgot to learn the material myself before offering to teach it. In giving students guidance as to when a standard RDBMS is likely to fall over and require investigation of parallel, clustered, distributed, or NoSQL approaches, I’d like to know roughly how many updates per second a standard RDBMS can process. Here are the criteria:

• mixture of inserts, updates, and selects, with the server doing 10 queries for every update and the typical update or insert involving two rows
• a 4U server with 8 CPU cores and enough RAM to hold the entire database
• eight hard drives so that transaction logs, indices, and tables can all reside on separate spindles (or magic RAID approaches can be used)
• perhaps a little bit of magic in the form of a solid-state drive being used for the transaction logs
• any RDBMS, including MySQL/InnoDB, Oracle, Sql Server, DB2, etc.

I’m looking for a number that is good to within one order of magnitude.

Thanks.

[http://www.tpc.org/tpce/results/tpce_perf_results.asp makes it look as though the answer is “about 2000” though I’m not sure if the TPC-E benchmark simultaneously requires some queries. It is tough to say because the tpc.org Web site is unusably slow…. I finally got the Word doc. It looks like they count some queries as “transactions”, e.g., “The [Customer-Position] transaction is a real-only transaction”. So maybe the answer is closer to 1000? The TPS-E benchmarks use some ridiculously expensive systems, but they also require a huge amount of data to be kept, e.g., 8 TB for a low-end system doing 2000 queries and updates/second.]

(The venerable TPC-C standard never struck me as matching up that well to typical Internet applications.)]

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One of my big mistakes as an investor was not seeing that a U.S. house price bubble deflation could affect the price of industrial equities (my main investment; I had faith in GE’s ability to sell jet engines in China and India even though I thought houses in Cincinnati were overvalued). Clearing off my desk from 2010, here’s a story from the Wall Street Journal (“Shareholders hit the roof over relocation subsidies”, October 25, 2010) about how whenever top managers at public companies change job, they’re compensated for any loss they might incur from selling their house. The Microsoft shareholders had to pay Stephen Elop $5.5 million in relocation costs, including $3.7 million to make up for the loss on his Los Altos mansion (separately, I would have loved to have gotten the $1.8 million furniture moving contract!).

How much will this take out of shareholders’ pockets? Let’s assume 5000 substantial public companies (e.g., the Wilshire 5000). Let’s assume that each company has 10 top executives, that turnover occurs every five years (2 execs per year), and that each one gets an average of $1 million if he or she sells a house in a down market. Peter Schiff in the WSJ on December 30, 2010 said they’d have to decline another 20 percent to get to the historical trend line (and Philip says the trend line itself is too high because it factors in continued robust growth for the U.S. economy, whereas in fact there has been little growth since 2007); the Dallas Federal Reserve Bank economists say another 23 percent drop is due. So let’s assume the down market in real estate lasts at least another 5 years. The Case-Shiller index peaked in 2006, so that means a total of 10 years of decline. That’s $2 million per public company per year and a total of $100 billion that will go to employees rather than shareholders.

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The figure above (click for larger version) is from an NSF study of K-12 math and science education and shows eighth graders’ math proficiency as a function of their mothers’ education level. I attended a presentation recently where the figure was used to show that schools should not be held responsible for the math ignorance of their graduates because kids with uneducated mothers were inevitably doomed to incompetence. My first thought upon seeing the figure was “Wow, the schools don’t teach any math at all; kids learn all of their math from Mom.”

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Readers have been sending me pointers to articles about the Motorola Atrix, a mobile phone with a laptop dock, and saying that it is similar to my 2005 article “Mobile Phone As Home Computer”. I don’t see the similarity because the Motorola dock has no hard drive and isn’t necessarily different than using a bluetooth keyboard and bluetooth display (does that work?) with any other smartphone. My idea of the dock was that it had its own monster CPU and graphics chips, unconstrained by power considerations, plus a hard drive for storing near-infinite video (the one form of data that a typical consumer might accumulate that is too large to be stored inexpensively in the cloud) and a removable hard drive mirror for backup.

Even if Motorola has not implemented my pet idea, this would seem to be a useful tool for travelers. Use the laptop dock when in a hotel or an office; use the phone by itself while walking around. Don’t carry any extra chargers or cables or extra weight from the full hard drive and circuitry of a typical laptop. I don’t like this for replacing a home PC because the 11″ screen on the laptop dock is so small. A $550 Dell home PC includes a 24″ “full HD” monitor with 1920×1080 resolution. That’s enough to view two pages of text side-by-side, a critical ability for students, certainly (one window for Wikipedia, from which to cut and paste into the other window, which holds the term paper).

Thoughts on the Atrix? Anything else from CES strike folks as interesting? There were a lot of tablet announcements, but I didn’t see much in the way of pricing. If a Netbook retails for $300, I would think that a $249 Android tablet would drive consumers truly wild, though this February 2010 analysis of iPad manufacturing cost makes it seem as though a high-performance $249 tablet is at least another year away.

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I recently rented a 2010 Nissan Altima Hybrid and drove it for about 250 mostly highway miles. When I topped it off for the return to Hertz, I found that it had averaged 28 miles per gallon, i.e., hardly better than the 7-passenger 1993 Dodge Grand Caravan that I owned. The Altima seated four in comfort and five if they didn’t mind getting friendly. The trunk could hold one standard suitcase plus a carry-on bag or two ; much of what would have been the trunk was apparently being used to hold batteries. I learned what 17 years of progress from the automotive industry looks like: going from 25 to 28 mpg while reducing the interior volume of the vehicle by half.

[Typical indicated highway driving speed was 70 mph, with the air conditioner on roughly 60 percent of the time. The trip included about 30 minutes of traffic jams due to an overturned vehicle (how would Southern Californians manage on the icy potholed roads of Massachusetts if they are flipping their vehicles over in broad daylight on perfectly dry and smooth Interstates?) and weekend traffic on a state highway going through what had been a small town and is now part of the endless strip mall sprawl.]

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A few interesting articles from the December 18, 2010 Economist magazine…

“Is it worth doing a PhD” notes that in Britain a man with a PhD earns 26 percent more than a man “who could have gone to university but chose not to” (i.e., a high school grad). In theory that extra 26 percent might make up for the 10+ years of lost wages during bachelor’s and graduate programs, but a man who gets a master’s degree earns a 23 percent premium. I.e., the difference in ultimate salary is nowhere near enough to make up for the lost wages of extra years in grad school and, in fact, in math and CS the premium does not exist. The economic damage of PhD programs is not limited to graduates, however. There are a huge number of dropouts and they tend to drop out after wasting many years in school (clinging “like limpets before eventually falling off”). As this is the Economist, the question of whether the PhD graduates might have had a lot of compensating fun during graduate school was not addressed.

In Economics Focus “Exploding misconceptions”, Barack Obama is quoted: “extremely poor societies…provide optimal breeding grounds for disease, terrorism and conflict.” The article cites studies by Alan Krueger of Princeton and Claude Berrebit of the RAND Corporation as well as surveys by the Pew Global Attitudes Project. Jihadists, including suicide bombers, turned out to have higher incomes and more education than average within their societies, e.g., in Lebanon or among the Palestinians in the West Bank and Gaza. The surveys of Muslims found that those with the most education were more likely to agree that suicide bombing against Western targets in Iraq was justified. As far as producing terrorists go, “citizens of the poorest countries were the least likely to commit a suicide attack”. (This dovetails with my November 2009 post “Who finances the Taliban and Al-Qaeda? We do.”)

Iceland, which let its banks fail, is compared to Ireland, which took on government debt to bail out its banks. Iceland had a painful brief period of adjustment and now is doing better than Ireland. (story)

The cover story “The U-bend of life” is about how average human happiness varies with age. Old people and young people are happy. The middle aged are miserable, with a reduction in happiness that starts around age 25, dips to a nadir at 46, and begins to rise again around 60. These data were adjusted for the presence of children and other responsibilities, supposedly. Tying this back to the first article discussed in this post, better educated people are happier, but the effect disappears when adjusted for income. A plumber or electrician who earns the same as a Ph.D. will be just as happy. [I guess one could argue that plumbing skill is in fact a “better education” than an abstruse Ph.D.]

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Here are my ideas for last-minute Christmas gifts, almost all of which are available at Amazon.com:

cheap

• book for food/diet/photography nerds: What I Eat: Around the World in 80 Diets
• book for nature lovers: Natural History (big grids of nicely printed photos of dozens of different animals or plants on each page)
• book for dog owners: 101 Dog Tricks
• toy for young kid: Plush Border Collie (very realistic except that it doesn’t bite you 50 times daily, eat your shoes, and display other signs of criminal insanity)
• for the kid who graduated in June and remains unemployed: The Book of U.S. Government Jobs
• for investors: A Random Walk Down Wall Street (the classic, updated to reflect the Collapse of 2008)

expensive

• mother of all toaster ovens: Breville BOV800XL (way faster (due to convection) and more convenient (due to integrated timer) than a standard oven)
• best all-around compact camera: Canon S95
• mobile phone with the best screen for viewing photos: Samsung Epic 4G (Organic LED screen, unique among smartphones; real keyboard; order with two extra batteries and three chargers unless recipient lives in a very good Sprint coverage area)
• tablet computer for someone who wants to carry it in a pocket and listen to music: Creative ZIIO 7 (half the price of an iPad; should also run any Android application)
• great sound in a small convenient package: Bowers & Wilkins iPod Dock (same concept as the Bose systems, but engineered by the world’s leading speaker company (B&W is an English company that makes most of the $10,000 monitors used in recording studios))

aviation-related

• book for helicopter nerds: The Helicopter: Thinking Forward, Looking Back (some real aerodynamics)
• for a pilot: an ebook reader for viewing approach plates, either the Kindle (cheap, very sharp screen, near-infinite battery life) or iPad Tablet (expensive, screen slightly blurry due to color LCD technology, shorter battery life, more flexible and capable than Kindle)

Folks: please use the comments section to post your best Christmas gift ideas.

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A U.S. Navy officer sent me the following video illustrating U.S. Air Force promotion procedures: youtube.

I’m not sure if they will blame WikiLeaks for this one…

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