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android fragment- How to save states of views in a fragment when another fragment is pushed on top o
... Now on hitting back FragA comes to the top and the onCreateView() is called. Now I had FragA in a particular state before FragB got pushed on top of it.
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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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Convert varchar to uniqueidentifier in SQL Server
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I was really hoping this would not be the solution but I guess we'll find out soon...
– grenade
Sep 7 '09 at 16:39
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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...
Best way to test exceptions with Assert to ensure they will be thrown
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Although your code is functionally sound I do not recommend using the ExpectedException attribute (since it's too constraining and error-prone) or to write a try/catch block in each test (since it's too complicated and error-prone). Use a well-designed as...
ROW_NUMBER() in MySQL
...mmonly-asked SQL questions (since it seems like it should be easy, but actually it kind of isn't).
I often plump for a null-self-join:
SELECT t0.col3
FROM table AS t0
LEFT JOIN table AS t1 ON t0.col1=t1.col1 AND t0.col2=t1.col2 AND t1.col3>t0.col3
WHERE t1.col1 IS NULL;
“Get the rows in the...
Redefine tab as 4 spaces
...ab characters in your file to appear 4 spaces wide, or by "tab" do you actually mean an indent, generated by pressing the tab key, which would result in the file literally containing (up to) 4 space characters for each "tab" you type?
Depending on your answer, one of the following sets of
settings ...
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 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...