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count(*) vs count(column-name) - which is more correct? [duplicate]
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COUNT(*) counts all rows
COUNT(column) counts non-NULLs only
COUNT(1) is the same as COUNT(*) because 1 is a non-null expressions
Your use of COUNT(*) or COUNT(column) should be based on the desired output only.
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Why does Javascript's regex.exec() not always return the same value? [duplicate]
... matches by performing the assignment as the loop condition.
var re = /foo_(\d+)/g,
str = "text foo_123 more text foo_456 foo_789 end text",
match,
results = [];
while (match = re.exec(str))
results.push(+match[1]);
DEMO: http://jsfiddle.net/pPW8Y/
If you don't like the placem...
How do I show a Save As dialog in WPF?
...alog dialog = new SaveFileDialog()
{
Filter = "Text Files(*.txt)|*.txt|All(*.*)|*"
};
if (dialog.ShowDialog() == true)
{
File.WriteAllText(dialog.FileName, fileText);
}
share
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improve th...
Rename multiple files based on pattern in Unix
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Not present on all *nix systems. Not on Max OS X for one, and no package in fink to get it. Haven't looked at MacPorts.
– dmckee --- ex-moderator kitten
Jul 6 '09 at 16:07
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lenses, fclabels, data-accessor - which library for structure access and mutation is better
...f these libraries also provide a bunch of extra combinators on top, and usually some form of template haskell machinery to automatically generate lenses for the fields of simple record types.
With that in mind, we can turn to the different implementations:
Implementations
fclabels
fclabels is pe...
Getting key with maximum value in dictionary?
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@oba2311 max_value = max(stats.values()); {key for key, value in stats.items() if value == max_value}
– A. Coady
Apr 4 '17 at 0:37
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What is the difference between lock and Mutex?
...hine.
bool firstInstance;
Mutex mutex = new Mutex(false, @"Local\DASHBOARD_MAIN_APPLICATION", out firstInstance);
if (!firstInstance)
{
//another copy of this application running
}
else
{
//run main application loop here.
}
// Refer to the mutex down here so garbage collection doesn't chu...
How can I get rid of an “unused variable” warning in Xcode?
...as an "unused" attribute you can use to suppress that warning:
BOOL saved __attribute__((unused)) = [moc save:&error];
Alternatively (in case LLVM doesn't support the above), you could split the variable declaration into a separate line, guaranteeing that the variable would be "used" whether ...
How to set focus on input field?
...nction ($timeout, $parse) {
return {
//scope: true, // optionally create a child scope
link: function (scope, element, attrs) {
var model = $parse(attrs.focusMe);
scope.$watch(model, function (value) {
console.log('value=', value);
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How to run a Runnable thread in Android at defined intervals?
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Alex, i have one small doubt.Now the thread is running perfectly and displaying the text continously, if i want to stop this means what i have to do?Please help me.
– Rajapandian
Dec 17 '09 at 14:19
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