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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...
Get first day of week in SQL Server
...e saying, how many weeks have passed since Monday, January 1, 1900? Let's call that [n]. Ok, now add [n] weeks to Monday, January 1, 1900. You should not be surprised that this ends up being a Monday. DATEADD has no idea that you want to add weeks but only until you get to a Sunday, it's just adding...
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 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...