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How to select the nth row in a SQL database table?
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There are ways of doing this in optional parts of the standard, but a lot of databases support their own way of doing it.
A really good site that talks about this and other things is http://troels.arvin.dk/db/rdbms/#select-limit.
Basically, PostgreSQL and MySQL supports the non-...
Utilizing multi core for tar+gzip/bzip compression/decompression
...r
tar -P --transform='s@/my/path/@@g' -cf - {} +
--transform is a simple string replacement parameter. It will strip the path of the files from the archive so the tarball's root becomes the current directory when extracting. Note that you can't use -C option to change directory as you'll lose bene...
Calling virtual functions inside constructors
... System.out.println( "Derived: " + x );
}
public static void main( String args[] ) {
Derived d = new Derived( 5 );
}
}
// outputs: Derived 0
// Derived 5
// ... so much for final attributes never changing :P
As you see, calling a polymorphic (virtual in C++ terminology) m...
Add x and y labels to a pandas plot
...abel')
plt.ylabel('ylabel')
plt.show()
Obviously you have to replace the strings 'xlabel' and 'ylabel' with what you want them to be.
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How to format a phone number with jQuery
...rhead, especially for something where the input format is known and simple string operations are FAR more efficient. And of course, there's the rule that using a regex for a problem just makes you have two problems.
– Marc B
Jan 6 '12 at 16:26
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Associative arrays in Shell scripts
...you can use test -z ${variable+x} (the x doesn't matter, that could be any string). For an associative array in Bash, you can do similar; use test -z ${map[key]+x}.
– Brian Campbell
Feb 6 '14 at 5:00
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How do you test to see if a double is equal to NaN?
... the following code.
public class Not_a_Number {
public static void main(String[] args) {
// TODO Auto-generated method stub
String message = "0.0/0.0 is NaN.\nsimilarly Math.sqrt(-1) is NaN.";
String dottedLine = "------------------------------------------------";
D...
What is a classpath and how do I set it?
...to go. I generally make sure my CLASSPATH environment variable is an empty string where I develop, whenever possible, so that I avoid global classpath issues (some tools aren't happy when the global classpath is empty though - I know of two common, mega-thousand dollar licensed J2EE and Java servers...
json_encode() escaping forward slashes
...ript> tags it's necessary as a </script> anywhere - even inside a string - will end the script tag.
Depending on where the JSON is used it's not necessary, but it can be safely ignored.
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Javascript / Chrome - How to copy an object from the webkit inspector as code
...ecursive object, you will get [object Object]. The way out is to copy(JSON.stringify(temp1)) , the object will be fully copied to your clipboard as a valid JSON, so you'd be able to format it as you wish, using one of many resources.
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