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Set value to NULL in MySQL
... can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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Regex doesn't work in String.matches()
I have this small piece of code
9 Answers
9
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C++ performance challenge: integer to std::string conversion
... val /= 10;
}
return s;
}
This will blow up on systems that disallow unaligned memory accesses (in which case, the first unaligned assignment via *(short*) would cause a segfault), but should work very nicely otherwise.
One important thing to do is to minimize the use of std::string. (I...
How to hide action bar before activity is created, and then show it again?
...tActionBar().hide();
setContentView(R.layout.splash); // be sure you call this AFTER requestFeature
This creates the ActionBar and immediately hides it before it had the chance to be displayed.
But now there is another problem. After putting windowActionBar="false" in the theme, the Activity...
New self vs. new static
...the first method, whereas static is bound to the called class (also see get_called_class()).
class A {
public static function get_self() {
return new self();
}
public static function get_static() {
return new static();
}
}
class B extends A {}
echo get_class(B::ge...
How to detect the device orientation using CSS media queries?
...n portrait orientation will cause the viewport to become wider than it is tall, thereby causing the browser to use landscape styles instead of portrait.
– Johann Combrink
Mar 10 '17 at 8:58
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Does BroadcastReceiver.onReceive always run in the UI thread?
...p, I create a custom BroadcastReceiver and register it to my Context manually via Context.registerReceiver . I also have an AsyncTask that dispatches notifier-Intents via Context.sendBroadcast . The intents are sent from a non-UI worker thread, but it seems that BroadcastReceiver.onReceive (...
Is there a goto statement in Java?
...ll not even compile in the present, and it remains possible to make it actually do something later on, without breaking existing code.
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Scala @ operator
...n itself? That would be accomplished with this:
o match {
case x @ Some(_) => println(x)
case None =>
}
Note that @ can be used at any level, not just at the top level of the matching.
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How to sort with a lambda?
...nclude <iostream>
#include <sstream>
struct Foo
{
Foo() : _i(0) {};
int _i;
friend std::ostream& operator<<(std::ostream& os, const Foo& f)
{
os << f._i;
return os;
};
};
typedef std::vector<Foo> VectorT;
std::string ...