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Swift - which types to use? NSString or String
...e NSString parameters and vice versa, some methods seem to not be automatically bridged as of this moment. See this answer for a discussion on how to get the a String's length and this answer for a discussion on using containsString() to check for substrings. (Disclaimer: I'm the author for both of ...
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
...
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...
How do I get the MAX row with a GROUP BY in LINQ query?
... (s => s.uid, tv => tv.uid, asdf => asdf.uid). Linq will automatically recognize it as selecting over elements of type Serial.
– Michael
Mar 17 '11 at 17:03
add a com...
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...
Could not load file or assembly 'System.Data.SQLite'
I've installed ELMAH 1.1 .Net 3.5 x64 in my ASP.NET project and now I'm getting this error (whenever I try to see any page):
...
How to create a custom exception type in Java? [duplicate]
... flag a problematic situation that should be handled by the developer who calls your method. It should be possible to recover from such an exception. A good example of this is a FileNotFoundException. Those exceptions are subclasses of Exception.
Unchecked exceptions are meant to represent a bug in ...
When to use extern in C++
...larify, using extern int x; tells the compiler that an object of type int called x exists somewhere. It's not the compilers job to know where it exists, it just needs to know the type and name so it knows how to use it. Once all of the source files have been compiled, the linker will resolve all of ...
How do I tell matplotlib that I am done with a plot?
...
You can use plt.close()/pylab.close() to remove all old figures
– Calvin1602
Jan 24 '13 at 8:32
2
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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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