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Is it a good idea to index datetime field in mysql?
...y in queries. If your only condition is BETWEEN NOW() AND DATE_ADD(NOW(), INTERVAL 30 DAY) and you have no other index in the condition, MySQL will have to do a full table scan on every query. I'm not sure how many rows are generated in 30 days, but as long as it's less than about 1/3 of the total...
What is the use of a private static variable in Java?
...you were to make something like:
public class Person
{
private static int numberOfEyes;
private String name;
}
and then you wanted to change your name, that is fine, my name stays the same. If, however you wanted to change it so that you had 17 eyes then everyone in the world would also ...
Java Equivalent of C# async/await?
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@user960567: No, my point is that it's a language feature - it can't be put solely in libraries. I don't believe there's any equivalent scheduled for Java 8 at least.
– Jon Skeet
May 14 '13 at 9:23
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Error to install Nokogiri on OSX 10.9 Maverick?
...N_C_SOURCE -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings -Wno-missing-field-initializers -Wshorten-64-to-32 -Wno-long-long -fno-common -pipe -g -DXP_UNIX -O3 -Wall -Wcast-qual -Wwrite-strings -Wconversion -Wmissing-noreturn -Winline -DNOKOGIRI_USE_PACK...
How to access pandas groupby dataframe by key
...0.528172 11
4 foo 0.865408 14
Note: This doesn't require creating an intermediary dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating the naive dictionary with dict(iter(gb)). This is because it uses data-structures already available in ...
Unit test naming best practices [closed]
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Resharper and IntelliJ both would probably find your test method and offer to rename it for you if you refactored/renamed using those tools. The also try to look in comments where you mention the method name and update those too.
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How do I configure a Python interpreter in IntelliJ IDEA with the PyCharm plugin?
There is a tutorial in the IDEA docs on how to add a Python interpreter in PyCharm, which involves accessing the "Project Interpreter" page. Even after installing the Python plugin, I don't see that setting anywhere.
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What is the coolest thing you can do in
...a series of animated onscreen characters that can be manipulated via a COM interface. You can download the code and characters at the Microsoft Agent download page.
The folllowing few lines will make the Merlin character appear on screen, fly around, knock on the screen to get your attention, and s...
Capturing Ctrl-c in ruby
...s, it does so by raising SystemExit. When a control-C comes in, it raises Interrupt. Since both SystemExit and Interrupt derive from Exception, your exception handling is stopping the exit or interrupt in its tracks. Here's the fix:
Wherever you can, change
rescue Exception => e
# ...
end
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Embedding DLLs in a compiled executable
Is it possible to embed a pre-existing DLL into a compiled C# executable (so that you only have one file to distribute)? If it is possible, how would one go about doing it?
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