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ALTER TABLE to add a composite primary key
I have a table called provider . I have three columns called person , place , thing . There can be duplicate persons, duplicate places, and duplicate things, but there can never be a dupicate person-place-thing combination.
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LINQ: Select an object and change some properties without creating a new object
...erties of a LINQ query result object without creating a new object and manually setting every property. Is this possible?
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How can I toggle word wrap in Visual Studio?
...rd Wrap (Ctrl+E, Ctrl+W)
General settings: Tools / Options / Text Editor / All Languages / Word wrap
Or search for 'word wrap' in the Quick Launch box.
Known issues:
If you're familiar with word wrap in Notepad++, Sublime Text, or Visual Studio Code, be aware of the following issues where Visual S...
Preferred way to create a Scala list
...do so with a tail-recursive function, foldLeft, or something else is not really relevant.
If you get the elements in the same order you use them, then a ListBuffer is most likely a preferable choice, if performance is critical.
But, if you are not on a critical path and the input is low enough, yo...
How do I get the opposite (negation) of a Boolean in Python?
...ful if you want to use a function that requires a predicate-function or a callback.
For example map or filter:
>>> lst = [True, False, True, False]
>>> list(map(operator.not_, lst))
[False, True, False, True]
>>> lst = [True, False, True, False]
>>> list(filter...
Is there any Rails function to check if a partial exists?
..., I'm using the following in my Rails 3/3.1 projects:
lookup_context.find_all('posts/_form').any?
The advantage over other solutions I've seen is that this will look in all view paths instead of just your rails root. This is important to me as I have a lot of rails engines.
This also works in R...
How can you use optional parameters in C#?
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Good on you for providing up-to-date information. Ideally the original answers would be updated with current information such as C# 4.0. I believe that is what the SO guys originally had in mind, a Wiki mentality, but everyone is a bit too afraid to edit someone else's answer.
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jQuery date formatting
...stion. It works well for me in a slightly different syntax/context:
var dt_to = $.datepicker.formatDate('yy-mm-dd', new Date());
If you decide to utilize datepicker from JQuery UI, make sure you use proper references in your document's < head > section:
<link rel="stylesheet" href="http...
Make a borderless form movable?
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This article on CodeProject details a technique. Is basically boils down to:
public const int WM_NCLBUTTONDOWN = 0xA1;
public const int HT_CAPTION = 0x2;
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam...
Test if lists share any items in python
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Short answer: use not set(a).isdisjoint(b), it's generally the fastest.
There are four common ways to test if two lists a and b share any items. The first option is to convert both to sets and check their intersection, as such:
bool(set(a) & set(b))
Because sets are stor...