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What's the best practice for primary keys in tables?
...ary. Prefer a numeric type because numeric types are stored in a much more compact format than character formats. This is because most primary keys will be foreign keys in another table as well as used in multiple indexes. The smaller your key, the smaller the index, the less pages in the cache you ...
What does a tilde do when it precedes an expression?
... 0000 0000 0000 0001
If it were a negative number, it'd be stored in 2's complement: invert all bits and add 1.
...and then flips all its bits...
1111 1111 1111 1111 1111 1111 1111 1110
So what is the use of it, then? When might one ever use it?
It has a quite a few uses. If you're writin...
How to insert text at beginning of a multi-line selection in vi/Vim
In Vim , how do I insert characters at the beginning of each line in a selection?
13 Answers
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Computed read-only property vs function in Swift
...ons (or methods) when actual work is being done. Maybe something has to be computed or read from disk or from a database: In this case I use a function, even when only a simple value is returned. That way I can easily see whether a call is cheap (properties) or possibly expensive (functions).
We w...
How to bind a List to a ComboBox?
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
Error while installing json gem 'mkmf.rb can't find header files for ruby'
...is no ruby development environment installed. Development env is needed to compile ruby extensions, which are mostly written in C. Proxy has nothing to do with the problem: everything is downloaded fine, just compilation fails.
I would suggest you to install ruby-dev (ruby-devel for rpm-based distr...
Remove empty lines in text using Visual Studio
How to remove empty lines in Visual Studio?
11 Answers
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When should the volatile keyword be used in C#?
...good article on Double Checked Locking, and briefly touches on this topic:
http://en.wikipedia.org/wiki/Double-checked_locking
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Python __call__ special method practical example
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Why prefer two's complement over sign-and-magnitude for signed numbers?
I'm just curious if there's a reason why in order to represent -1 in binary, two's complement is used: flipping the bits and adding 1?
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