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Fastest way to count exact number of rows in a very large table?
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Nope, COUNT(*) = COUNT(key). This is just wrong. If there is no NOT NULL constraint - then they can be not equal (in results as well as in execution plan).
– zerkms
May 20 '11 at 8:28
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How can I set focus on an element in an HTML form using JavaScript?
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Do this.
If your element is something like this..
<input type="text" id="mytext"/>
Your script would be
<script>
function setFocusToTextBox(){
document.getElementById("mytext").focus();
}
</script>
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Beyond Stack Sampling: C++ Profilers
...ue will reveal portions of your code that are CPU bound. Which is awesome if that is the bottle neck in your application. Not so great if your application threads spend most of their time fighting over a mutex.
A time sampling profiler grabs a stack trace every N microseconds.
This technique will ...
Android destroying activities, killing processes
... not be resumed until this method
returns. Followed by either onResume() if the activity returns back to
the front, or onStop() if it becomes invisible to the user.
onStop() Called when the activity is no longer visible to the user, because another activity has been resumed and is covering ...
Error when deploying an artifact in Nexus
Im' getting an error when deploying an artifact in my own repository in a Nexus server: "Failed to deploy artifacts: Could not transfer artifact" "Failed to transfer file http:///my_artifact. Return code is: 400"
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How to stop mysqld
...Or:
sudo /usr/local/mysql/bin/mysqld stop
Or:
sudo mysql.server stop
If you install the Launchctl in OSX you can try:
MacPorts
sudo launchctl unload -w /Library/LaunchDaemons/org.macports.mysql.plist
sudo launchctl load -w /Library/LaunchDaemons/org.macports.mysql.plist
Note: this is persi...
Java: Difference between the setPreferredSize() and setSize() methods in components
What is the main difference between setSize() and setPreferredSize() . Sometimes I used setSize() , sometimes setPreferredSize() , sometimes one does what I want, sometimes the other.
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Is there a CSS selector by class prefix?
...nt to apply a CSS rule to any element whose one of the classes matches specified prefix.
4 Answers
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html (+css): denoting a preferred place for a line break
...n blocks by space you need to place it between inline-blocks. For example, if spans were styled to become inline-blocks, then <span>Hello </span><span> world</span> will be Helloworld, and <span>Hello</span> <span>world</span> will be normal Hello worl...
URL to load resources from the classpath in Java
In Java, you can load all kinds of resources using the same API but with different URL protocols:
14 Answers
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