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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
If I have a table
15 Answers
15
...
Passing multiple error classes to ruby's rescue clause in a DRY fashion
...operator *.
EXCEPTIONS = [FooException, BarException]
begin
a = rand
if a > 0.5
raise FooException
else
raise BarException
end
rescue *EXCEPTIONS
puts "rescued!"
end
If you are going to use a constant for the array as above (with EXCEPTIONS), note that you cannot define it w...
Print function log /stack trace for entire program using firebug
...nt.exist += 0; //doesn't exist- that's the point
} catch (e) {
if (e.stack) { //Firefox / chrome
var lines = e.stack.split('\n');
for (var i = 0, len = lines.length; i < len; i++) {
callstack.push(lines[i]);
}
//Remov...
How do I work around JavaScript's parseInt octal behavior?
...
This is a common Javascript gotcha with a simple solution:
Just specify the base, or 'radix', like so:
parseInt('08',10); // 8
You could also use Number:
Number('08'); // 8
share
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impro...
What is the advantage of using async with MVC5?
What is the difference between:
3 Answers
3
...
curl -GET and -X GET
Curl offers a series of different http method calls that are prefixed with a X, but also offers the same methods without. I've tried both and I can't seem to figure out the difference. Can someone explain to me quickly how these two operations differ?
...
indexOf method in an object array?
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It's not supported by IE8 but, if that's not a problem, this is the best solution.
– Antonio Laguna
Nov 22 '13 at 11:56
64
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How to check if the string is empty?
... they are considered false in a Boolean context, so you can just do this:
if not myString:
This is the preferred way if you know that your variable is a string. If your variable could also be some other type then you should use myString == "". See the documentation on Truth Value Testing for ot...
How do I execute a program from Python? os.system fails due to spaces in path
...
Here's a different way of doing it.
If you're using Windows the following acts like double-clicking the file in Explorer, or giving the file name as an argument to the DOS "start" command: the file is opened with whatever application ...
PHP string “contains” [duplicate]
...
if (strpos($str, '.') !== FALSE)
{
echo 'Found it';
}
else
{
echo 'Not found.';
}
Note that you need to compare with the !== operator. If you use != or <> and the '.' is found at position 0, hey! 0 compares equal to...