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MySQL DISTINCT on a GROUP_CONCAT()
...d Jun 21 '10 at 9:47
Daniel Vassallo
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answered Jun 21 '10 at 9:41
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Ruby: kind_of? vs. instance_of? vs. is_a?
...metimes. Think @honda.kind_of? Car and @person.is_a? Administrator, Ruby's all about the aesthetics. In fact, notice the grammatical error... with active support you can write @person.is_an? Administrator :)... That might have made it into Ruby core by now, actually.
– rfunduk
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Escaping keyword-like column names in Postgres
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Some warning: Without the quotes PostgreSQL folds all identifiers to lowercase. MyTable, myTable and mytable are just the same. With the quotes this folding is not done. So "MyTable" is no more the same as mytable.
– A.H.
Oct 4 '11 at 1...
What are fixtures in programming?
...ment in which tests are run so that results are
repeatable. Some people call this the test context.
Examples of fixtures:
Loading a database with a specific, known set of data
Erasing a hard disk and installing a known clean operating system installation
Copying a specific known s...
Asterisk in function call
...as input, and expands it into actual positional arguments in the function call.
So if uniqueCrossTabs was [ [ 1, 2 ], [ 3, 4 ] ], then itertools.chain(*uniqueCrossTabs) is the same as saying itertools.chain([ 1, 2 ], [ 3, 4 ])
This is obviously different from passing in just uniqueCrossTabs. In yo...
LINUX: Link all files from one to another directory [closed]
I want to link ( ln -s ) all files that are in /mnt/usr/lib/ into /usr/lib/
4 Answers
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How to use IntelliJ IDEA to find all unused code?
When I am in a .java file the unused code is usually grayed out or has a green underline saying this code will probably (probably because of some weird JNI/Reflection corner cases) be unused. But I have this project with thousands of Java files and I want to find ALL INSTANCES of such probable-unuse...
Why is conversion from string constant to 'char*' valid in C but invalid in C++
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As of C++11, the implicit conversion that had been deprecated was officially removed, so code that depends on it (like your first example) should no longer compile.
You've noted one way to allow the code to compile: although the implicit conversion has been removed, an explicit conversion still ...
How to merge a list of lists with same type of items to a single list of items?
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Why is x => x needed for this to work? I usually see things like x = > x +1 but not x = > x.
– SwimBikeRun
Apr 18 '15 at 2:25
9
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C++ where to initialize static const
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Anywhere in one compilation unit (usually a .cpp file) would do:
foo.h
class foo {
static const string s; // Can never be initialized here.
static const char* cs; // Same with C strings.
static const int i = 3; // Integral types can be initialized...