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How to add column if not exists on PostgreSQL?
Question is simple. How to add column x to table y , but only when x column doesn't exist ? I found only solution here how to check if column exists.
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How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
(Note: This question is about not having to specify the number of elements and still allow nested types to be directly initialized.)
This question discusses the uses left for a C array like int arr[20]; . On his answer , @James Kanze shows one of the last strongholds of C arrays, it's unique i...
java: ArrayList - how can i check if an index exists?
I'm using ArrayList<String> and I add data at specific indices,
how can I check if a specific index exists?
11 Ans...
Writing a list to a file with Python
Is this the cleanest way to write a list to a file, since writelines() doesn't insert newline characters?
21 Answers
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C# Lazy Loaded Automatic Properties
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No there is not. Auto-implemented properties only function to implement the most basic of properties: backing field with getter and setter. It doesn't support this type of customization.
However you can use the 4.0 Lazy<T> ...
How to hide one item in an Android Spinner
I am looking for a way to hide one item in an Android spinner widget. This would allow you to simulate a spinner with no items selected, and ensures that the onItemSelected() callback is always called for every item selected (if the hidden item is the "current" one). Normally there is always one ite...
Disable assertions in Python
How do I disable assertions in Python?
6 Answers
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ExecutorService, how to wait for all tasks to finish
What is the simplest way to to wait for all tasks of ExecutorService to finish? My task is primarily computational, so I just want to run a large number of jobs - one on each core. Right now my setup looks like this:
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“Origin null is not allowed by Access-Control-Allow-Origin” error for request made by application ru
...URL. There are two ways for CORS headers to signal that a cross-domain XHR is OK. One is to send Access-Control-Allow-Origin: * (which, if you were reaching Flickr via $.get, they must have been doing) while the other was to echo back the contents of the Origin header. However, file:// URLs produce ...
Dealing with “java.lang.OutOfMemoryError: PermGen space” error
Recently I ran into this error in my web application:
32 Answers
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