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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...cit, so you can get away with a slightly dumber optimizer.
When in doubt, test!
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How can I determine if a variable is 'undefined' or 'null'?
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I'm trying to test if event is null in firefox and an error blocks the execution: "event is undefined"
– Entretoize
Sep 6 '18 at 10:32
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When is a Java method name too long? [closed]
...ot be too long. I do want to add one exception though:
The names of JUnit test methods, however, can be long and should resemble sentences.
Why?
Because they are not called in other code.
Because they are used as test names.
Because they then can be written as sentences describing requirements. ...
Why can't overriding methods throw exceptions broader than the overridden method?
...den method declares the exception
Example:
class Super {
public void test() {
System.out.println("Super.test()");
}
}
class Sub extends Super {
@Override
public void test() throws IndexOutOfBoundsException {
// Method can throw any Unchecked Exception
Syste...
How to determine whether an object has a given property in JavaScript
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Object has property:
If you are testing for properties that are on the object itself (not a part of its prototype chain) you can use .hasOwnProperty():
if (x.hasOwnProperty('y')) {
// ......
}
Object or its prototype has a property:
You can use the i...
Maven: The packaging for this project did not assign a file to the build artifact
...very cycle leading up to and including the install (like compile, package, test, etc.). The latter will not even compile or package your code, it will just run that one goal. This kinda makes sense, looking at the exception; it talks about:
StarTeamCollisionUtil: The packaging for this project d...
Which selector do I need to select an option by its text?
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This could help:
$('#test').find('option[text="B"]').val();
Demo fiddle
This would give you the option with text B and not the ones which has text that contains B. Hope this helps
For recent versions of jQuery the above does not work. As comm...
How to check if a file is a valid image file?
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That won't be sufficient if he's really testing for "valid" images; the presence of a magic number doesn't guarantee that the file hasn't been truncated, for example.
– Ben Blank
May 20 '09 at 18:11
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How to find the operating system version using JavaScript?
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oscpu worked inconsistently for me when I tested it across the 4 major browsers on Windows 7. @Ludwig's solution worked consistently.
– Ian Ippolito
Jan 24 '14 at 21:04
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Fastest method to replace all instances of a character in a string [duplicate]
What is the fastest way to replace all instances of a string/character in a string in JavaScript? A while , a for -loop, a regular expression?
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