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PostgreSQL Crosstab Query
...
Install the additional module tablefunc once per database, which provides the function crosstab(). Since Postgres 9.1 you can use CREATE EXTENSION for that:
CREATE EXTENSION IF NOT EXISTS tablefunc;
Improved test case
CREATE ...
Android: failed to convert @drawable/picture into a drawable
In my drawable folder I have a few images and they all reference perfect, but when I try and add any more images with the exact same size in the same folder, and try to reference it, is flags up an error "Failed to convert @drawable/picture into a drawable" . I have tried the same image with a diff...
What is the fastest way to check if a class has a function defined?
...tr() to get the attribute, and callable() to verify it is a method:
invert_op = getattr(self, "invert_op", None)
if callable(invert_op):
invert_op(self.path.parent_op)
Note that getattr() normally throws exception when the attribute doesn't exist. However, if you specify a default value (None...
cleanest way to skip a foreach if array is empty [duplicate]
...t need:
foreach ((array) $items as $item) {
print $item;
}
Note: to all the people complaining about typecast, please note that the OP asked cleanest way to skip a foreach if array is empty (emphasis is mine). A value of true, false, numbers or strings is not considered empty.
In addition, th...
C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
Print string to text file
...t_file.close()
If you use a context manager, the file is closed automatically for you
with open("Output.txt", "w") as text_file:
text_file.write("Purchase Amount: %s" % TotalAmount)
If you're using Python2.6 or higher, it's preferred to use str.format()
with open("Output.txt", "w") as text...
How to determine height of UICollectionView with FlowLayout
...y question: I was completely searching in the wrong place, digging through all the documentation I could find on UICollectionView.
The simple and easy solution lies in the underlying layout: Just call collectionViewContentSize on your myCollectionView.collectionViewLayout property and you get the h...
What is Node.js? [closed]
I don't fully get what Node.js is all about. Maybe it's because I am mainly a web based business application developer. What is it and what is the use of it?
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Routes with Dash `-` Instead of Underscore `_` in Ruby on Rails
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there has to be a better and faster way to convert all routes that has undersore to hyphens
– carbonr
Mar 31 '13 at 17:59
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Fatal error: “No Target Architecture” in Visual Studio
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_WIN32 identifier is not defined.
use #include <SDKDDKVer.h>
MSVS generated projects wrap this include by generating a local "targetver.h"which is included by "stdafx.h" that is comiled into a precompiled-header throu...