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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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How do I use FileSystemObject in VBA?
...set a reference to the VB script run-time library.
The relevant file is usually located at \Windows\System32\scrrun.dll
To reference this file, load the
Visual Basic Editor (ALT+F11)
Select Tools > References from the drop-down menu
A listbox of available references will be displayed
Tick the c...
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...
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...
no gravity for scrollview. how to make content inside scrollview as center
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I had the same issue and finally figured it out. This is for a vertical ScrollView.
Put your ScrollView inside a RelativeLayout and center it in the RelativeLayout. In order for this to work, your ScrollView should have
android:layout_height="wrap_c...
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...
How is Generic Covariance & Contra-variance Implemented in C# 4.0?
...hat will become IEnumerable<out T>. That doesn't hurt type safety at all, but lets you return an IEnumerable<string> from a method declared to return IEnumerable<object> for instance.
Contravariance is harder to give concrete examples for using interfaces, but it's easy with a del...
MySQL Creating tables with Foreign Keys giving errno: 150
... CONSTRAINT's ON DELETE rule is SET NULL make sure the foreign key can actually be NULL! I spent 30 minutes reading this answer over and over, making sure my tables met the conditions but still getting Error 150. Then I noticed my FK was a NOT NULL field meaning the rule was impossible to apply.
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