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B-Tree vs Hash Table
In MySQL, an index type is a b-tree, and access an element in a b-tree is in logarithmic amortized time O(log(n)) .
5 Answ...
Shorten string without cutting words in JavaScript
I'm not very good with string manipulation in JavaScript, and I was wondering how you would go about shortening a string without cutting any word off. I know how to use substring, but not indexOf or anything really well.
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How to express infinity in Ruby?
...own constant using the following*:
I've checked that in Ruby 1.8.6, 1.8.7, and 1.9.2 you have Float.infinite?.
PositiveInfinity = +1.0/0.0
=> Infinity
NegativeInfinity = -1.0/0.0
=> -Infinity
CompleteInfinity = NegativeInfinity..PositiveInfinity
=> -Infinity..Infinity
*I've verified ...
Can Java 8 code be compiled to run on Java 7 JVM?
... code requires you to target a 1.8 VM. I just tried the new Java 8 release and tried compiling with -target 1.7 -source 1.8, and the compiler refuses:
$ javac Test -source 1.8 -target 1.7
javac: source release 1.8 requires target release 1.8
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How to get number of rows using SqlDataReader in C#
...defined except for one that states to do a while loop with Read() method and increment a counter.
6 Answers
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How do I insert datetime value into a SQLite database?
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When you format dates like this, date ordering and lexical ordering work out the same. E.g. '2008-02-01' > '2007-02-01', '2008-01-02' > '2008-01-01' both as strings and as dates. But you don't strictly need to care about this because SQLite ORDER BY will take care ...
File.separator vs FileSystem.getSeparator() vs System.getProperty(“file.separator”)?
...idden by calls to System.setProperty(String key, String value) or with command line parameters -Dfile.separator=/
File.separator gets the separator for the default filesystem.
FileSystems.getDefault() gets you the default filesystem.
FileSystem.getSeparator() gets you the separator character for ...
Return positions of a regex match() in Javascript?
...
if (match) {
console.log("match found at " + match.index);
}
And for multiple matches:
var re = /bar/g,
str = "foobarfoobar";
while ((match = re.exec(str)) != null) {
console.log("match found at " + match.index);
}
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Replace one character with another in Bash
...lexity is worse than linear. A small test: x="$(tr -dc 'a-z \n' </dev/urandom | head -c1M)"; time y="$(tr ' ' \\- <<< "$x")"; time z="${x// /-}". With a string length of 1M (=2^20) tr took 0.04s and bash 5.0.11 took 17s. With 2M tr took 0.07s (expected) but bash took 69s (4 times as lon...
How can I embed a YouTube video on GitHub wiki pages?
...o markup (though it's extremely easy to pickup). I am working on a package and am trying to get the wiki pages looking nice as a help manual. I can insert a YouTube video link into the wiki page pretty easily but how do I embed a YouTube video. I know this may not be possible.
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