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Best practices for SQL varchar column length [closed]
...n UK are usually between 1-35 characters. If you decide to make it varchar(64), you're not really going to hurt anything... unless you're storing this guy's family name that's said to be up to 666 characters long. In that case, maybe varchar(1028) makes more sense.
And in case it's helpful, here's ...
Passing command line arguments in Visual Studio 2010?
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What is the difference between NaN and None?
...n reason to use NaN (over None) is that it can be stored with numpy's float64 dtype, rather than the less efficient object dtype, see NA type promotions.
# without forcing dtype it changes None to NaN!
s_bad = pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype...
How to start an application without waiting in a batch file?
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Is returning null bad design? [closed]
... check for it and hence your code does not need to follow a different path based on the return value. You might want to check out the Null Object Pattern which provides more information on this.
For example, if I were to define a method in Java that returned a Collection I would typically prefer t...
Why use Gradle instead of Ant or Maven? [closed]
...ology Radar from October 2012:
Two things have caused fatigue with XML-based build tools like Ant and
Maven: too many angry pointy braces and the coarseness of plug-in
architectures. While syntax issues can be dealt with through
generation, plug-in architectures severely limit the ability ...
error opening HPROF file: IOException: Unknown HPROF Version
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Batch file to copy directories recursively
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Safe characters for friendly url [closed]
...od, I discovered today, is a bad choice of character to use for a URL-safe Base64 encoder, because there will be those rare cases where your encoded data may produce two consecutive dots (".."), which is significant in that it refers to the parent directory.
– pohl
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Generate random numbers following a normal distribution in C/C++
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Here's a C++ example, based on some of the references. This is quick and dirty, you are better off not re-inventing and using the boost library.
#include "math.h" // for RAND, and rand
double sampleNormal() {
double u = ((double) rand() / (RA...