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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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Java: Date from unix timestamp
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This is the right way:
Date date = new Date ();
date.setTime((long)unix_time*1000);
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Set the value of a variable with the result of a command in a Windows batch file
...%a in ('command1 ^| command2') do set VAR=%%a.
– Bill_Stewart
Mar 4 '16 at 19:23
@Bill_Stewart you just saved my day, ...
What does %w(array) mean?
....], curly braces %w{...} or even something like exclamation marks %w!...!. All of these have the same behavior (returning an array).
– ryanb
Aug 13 '09 at 21:40
146
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Django DB Settings 'Improperly Configured' Error
...--settings=mysite.settings (or whatever settings module you use)
Set DJANGO_SETTINGS_MODULE environment variable in your OS to mysite.settings
(This is removed in Django 1.6) Use setup_environ in the python interpreter:
from django.core.management import setup_environ
from mysite import settings
s...
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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How can I listen for a click-and-hold in jQuery?
...tartTrigger(e) {
var $elem = $(this);
$elem.data('mouseheld_timeout', setTimeout(function() {
$elem.trigger('mouseheld');
}, e.data));
}
function stopTrigger() {
var $elem = $(this);
clearTimeout($elem.data('mouseheld_timeout'));
}
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NGinx Default public www location?
...with Apache before, so I am aware that the default public web root is typically /var/www/ .
30 Answers
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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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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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