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MySQL: Fastest way to count number of rows
...mysql side?
If the COUNT(*) is slow, you should run EXPLAIN on the query, and check if indexes are really used, and where should they be added.
The following is not the fastest way, but there is a case, where COUNT(*) doesn't really fit - when you start grouping results, you can run into problem...
Wireshark localhost traffic capture [closed]
...ssible - read below. You can use the local address of your machine instead and then you'll be able to capture stuff. See CaptureSetup/Loopback.
Summary: you can capture on the
loopback interface on Linux, on
various BSDs including Mac OS X, and
on Digital/Tru64 UNIX, and you might
be abl...
What is the difference between __init__ and __call__?
I want to know the difference between __init__ and __call__ methods.
13 Answers
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What's the difference of “./configure” option “--build”, “--host” and “--target”?
The script ./configure accepts 3 options --build , --host and --target . I'm confusing their roles. What's the difference and semantics of them?
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Python function attributes - uses and abuses [closed]
Not many are aware of this feature, but Python's functions (and methods) can have attributes . Behold:
8 Answers
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Apple Mach-O Linker Error when compiling for device
I've just upgraded to xcode 4.0 and I can no longer deploy to iPhone, I get a Apple Mach-O Linker Error, it still works for the simulator though.
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How dangerous is it to compare floating point values?
...
First of all, floating point values are not "random" in their behavior. Exact comparison can and does make sense in plenty of real-world usages. But if you're going to use floating point you need to be aware of how it works. Erring on the side of assuming floating point ...
Wildcards in a Windows hosts file
..., I can just add vhosts to Apache called site1.local , site2.local etc, and have them all resolve to localhost , while Apache serves a different site accordingly.
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How to create a HashMap with two keys (Key-Pair, Value)?
...= 31 * result + y;
return result;
}
}
Implementing equals() and hashCode() is crucial here. Then you simply use:
Map<Key, V> map = //...
and:
map.get(new Key(2, 5));
Table from Guava
Table<Integer, Integer, V> table = HashBasedTable.create();
//...
table.get(2, 5);...
Visual Studio retrieving an incorrect path to a project from somewhere
Visual Studio (and possibly TFS) has somehow (I think perhaps during a source control merge) become confused about the path of a project within my solution.
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