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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.

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).

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