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Submission + - Result of a Simple SQL Indexing Quiz: 60% Fail (

An anonymous reader writes: The analysis of 28.000 results suggests that hardly anybody knows how to get indexes right. In the simple multiple-choice test, merely 38% passed — guessing alone would result in 12.5%. Just 10% managed to answer all five questions correctly. When the story broke on Reddit, doubts about the validity of the results were raised. On the one hand, people bring up examples to show that the quiz is actually wrong so the conclusion is wrong too. In the top voted comment, however, a Redditor admits “It's even worse, IMO. I, for instance, got 3 out 5. But I got 2 of them for the wrong reasons. So, in fact, I only knew the answer for 1 out of 5.” Could it really be that bad?

Comment A few free resources (Score 2) 106

Practical PostgreSQL:
Learn SQL The Hard Way:
Use The Index, Luke!: A Guide To SQL Database Performance: (my own site)

Submission + - Making SQL Fast: Use The Index, Luke! (

mws writes: SQL performance has been an issue ever since. Developers all over the world spend hours staring at SQL statements every day—just to figure out why some are running fast, but others are not. Use The Index, Luke! explains just that. It's a guide to SQL performance that puts all parts of SQL in context of the database performance workhorse: the index.

Submission + - Video Showing Half A Million Asteroid Discoveries (

An anonymous reader writes: Since 1980 over a half million asteroids have been discovered, mostly between the orbits of Mars and Jupiter, now thanks to this video you can see this activity condensed into a few minutes. At full resolution it's a mesmerizing experience as new discoveries are added and the video makes it possible to see patterns in the discovery positions, for example a large number appear in line between Earth and Jupiter as astronomers started looking for smaller jovian moons after Voyagers visit to the system.

Submission + - SPAM: Tata regrets the fall-out of Nano project

An anonymous reader writes: Tata group, one of the oldest industrial group, seems to be regretting the political agitation faced in the year 2008 at Singur due to which the company had to shift its Nano project to Sanand in Gujarat. The group's Chairman, Mr Ratan Tata said on Monday that he regrets that Tata Motors could not do the Nano car project which was scheduled for West Bengal.
Link to Original Source

Journal Journal: Use The Index, Luke!

Use The Index, Luke is a guide to database performance for developers. Unlike many other performance tuning resources, Use The Index, Luke avoids unnecessary details about database internals, but highlights the one topic that is most often neglected: proper indexing.

Comment Re:Say goodbye for XML (Score 1) 272

Are you serious? What kind of small company actually designs " they showed to Microsoft..." and doesn't expect

a) the ideas to be stolen by Microsoft.

b) be bought out by Microsoft.

c) be "corporate cannibalized" by Microsoft.


This was around the time that Microsoft was being tried and convicted on anti trust grounds in the U.S. and supposedly was reforming into a "kinder gentler" Microsoft that didn't resemble the black widow spider any more.

Comment Re:Why? (Score 2, Insightful) 283

In most of our lifetimes? Per Wikipedia:

The very large IPv6 address space supports a total of 2^128 (about 3.4×10^38) addresses--or approximately 5×10^28 (roughly 2^95) addresses for each of the roughly 6.5 billion (6.5×10^9) people alive in 2006. In a different perspective, this is 2^52 (about 4.5×10^15) addresses for every observable star in the known universe.

It will take way more than poor management to use up all those numbers in any timescale with meaning to a human life.

That quote from Wikipedia you pulled, is immediately followed by this:

"While these numbers are impressive, it was not the intent of the designers of the IPv6 address space to assure geographical saturation with usable addresses. Rather, the longer addresses allow a better, systematic, hierarchical allocation of addresses and efficient route aggregation."

If we could arbitrarily ignore the network structure and special ranges assigned in IPv4, we have 4.2 billion possible IP numbers (2^32). Do we have 4 billion computers on the Internet? No. Do we have IPv4 shortage? Yes. In fact we had IPv4 shortage even back in the early 90-s when Internet was far from being mainstream yet (which prompted the jump from classful network to CIDR).

Comment Re:They don't say "Java is bad" (Score 1) 1267

Read the text and you will notice that they claim that "Teaching Java, as the only language, is damaging." and that might be true.

Not exactly, the article says also:

The slogan is a reminder of how thinking habits of programmers are influenced by the first language they learn and how hard it is to shake these habits if you do all your programming in a single language.

And i have to admin that this is awfully true.

I started with Basic as a child, took me some years. it was then very easy to switch to pascal (one week) and further to c (another week). After that i thought, well i can learn C++ also in one week. Yep, i read the book in one week. And what i did was a little "C with classes" but i noticed only a year later. year after year i noticed that there is more about C++ then what i thought of. After three years i managed to use STL efficiently, used exceptions properly, managed inhertitance (including multiple & virtual inheritance), did use descrutctores and smart pointer and so on. so i thought it's over, i took me three years to learn C++.

But some years later, i read "Modern C++ Design" and noticed that there is still a lot more :)

to cut a long story short: the first programming paradigm you learn will influence (limit?) your way of thinging quite a while.

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