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SQL Server - When to use Clustered vs non-Clustered Index?
...stered and non clustered indexes and have an understanding of how they actually work. I understand how clustered and non-clustered indexes improve read performance. But one thing I am not sure is that what would be the reasons where I would choose one over the other.
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How do I create a SHA1 hash in ruby?
... of ruby. Worse yet, the string being passed to hexdigest isn't dynamic at all! This method would return the same hash regardless what data you give it!
– Blixxy
Jul 7 '12 at 10:10
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python numpy machine epsilon
...s of Python's builtin float. Python floats are 64-bit (C double) on almost all platforms. float and np.float64 therefore usually have equivalent precision, and for most purposes you can use them interchangeably. However they aren't identical - np.float64 is a numpy-specific type, and an np.float64 s...
invalid command code ., despite escaping periods, using sed
...of sed, the -i option expects an extension argument so your command is actually parsed as the extension argument and the file path is interpreted as the command code.
Try adding the -e argument explicitly and giving '' as argument to -i:
find ./ -type f -exec sed -i '' -e "s/192.168.20.1/new.domai...
Why do table names in SQL Server start with “dbo”?
At least on my local instance, when I create tables, they are all prefixed with "dbo.". Why is that?
3 Answers
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Why is the standard session lifetime 24 minutes (1440 seconds)?
...P3 days, PHP itself had no session support.
But an open-source library called PHPLIB, initially written by Boris Erdmann and Kristian Koehntopp from NetUSE AG, provided sessions via PHP3 code.
Session lifetimes were defined in minutes, not seconds. And the default lifetime was 1440 minutes, o...
Iterating Through a Dictionary in Swift
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If you want to iterate over all the values:
dict.values.forEach { value in
// print(value)
}
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How can you sort an array without mutating the original array?
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this is really great.i think easier to understand than the concat and other approaches
– sktguha
Aug 31 at 20:02
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How do you downgrade rubygems?
I have rubygems 1.3.1 installed but I want to go back to 1.2.0. What's the command to downgrade rubygems?
6 Answers
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Create whole path automatically when writing to a new file
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Use FileUtils to handle all these headaches.
Edit: For example, use below code to write to a file, this method will 'checking and creating the parent directory if it does not exist'.
openOutputStream(File file [, boolean append])
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