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Does MySQL index foreign key columns automatically?
...million records. This is ofc MySQL 5.1 InnoDB. The table has three fields, one is primary key integer, the other is already indexed. The third was a foreign key to primary key of another table. Without adding an explicit index, lookups took several seconds here. Show index from table also didn't sho...
How do Trigonometric functions work?
...cipes.
edit: Wikipedia has a semi-decent article on approximation theory. One of the sources they cite (Hart, "Computer Approximations") is out of print (& used copies tend to be expensive) but goes into a lot of detail about stuff like this. (Jack Ganssle mentions this in issue 39 of his newsl...
How do I daemonize an arbitrary script in unix?
...standard error to a different file of your choice. If you want to use just one file for both standard out and standard error you can us this:
nohup yourScript.sh script args >script.out 2>&1 &
The 2>&1 tells the shell to redirect standard error (file descriptor 2) to the same...
Why are const parameters not allowed in C#?
...rt of feature into any hypothetical future version of C#, if there even is one, which we have not announced one way or the other. It is something I would love to see, and something which the coming emphasis on multi-core computing might require, but none of this should be in any way construed to be ...
When is JavaScript's eval() not evil?
...ll compute the result during the parse rather than run another parser (the one inside eval()). But it may be easier to code using eval(), and the performance hit will probably be unnoticeable. It looks like eval() in this case is no more evil than any other function that could possibly save you some...
MIN/MAX vs ORDER BY and LIMIT
Out of the following queries, which method would you consider the better one? What are your reasons (code efficiency, better maintainability, less WTFery)...
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Why does std::getline() skip input after a formatted extraction?
...ty of your program, it follows that it must be skipped or ignored somehow. One option is to call std::cin.ignore() after the the first extraction. It will discard the next available character so that the newline is no longer in the way.
std::getline(std::cin.ignore(), state)
In-Depth Explanation:
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Optimal number of threads per core
...t number of threads until you find the right number for your application.
One thing for sure: 4k threads will take longer. That's a lot of context switches.
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When would you use the different git merge strategies?
...e is the default for non-fast-forward merges. We're all familiar with that one.
Octopus
I've used octopus when I've had several trees that needed to be merged. You see this in larger projects where many branches have had independent development and it's all ready to come together into a single he...
List passed by ref - help me explain this behaviour
...ed myList.Sort();
Finally, when you did: myList' = myList2, you lost the one of the reference but not the original and the collection stayed sorted.
If you use by reference (ref) then myList' and myList will become the same (only one reference).
Note: I use myList' to represent the parameter t...