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Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
...in BCNF because there is no column (either key or non-key) that is functionally dependent on anything besides that key.
Because each pizza must have exactly one of each topping type, we know that (Pizza, Topping Type) is a candidate key. We also know intuitively that a given topping cannot belong ...
CoffeeScript on Windows?
...y platform. The instructions are the same for Windows, Mac, or Linux
Install Nodejs from http://nodejs.org/
Install CoffeeScript globally with the node package manager npm install -g coffeescript or locally npm install --save-dev coffeescript
Write a script in your favourite text editor. Save it, ...
If list index exists, do X
... that relative index from the end of the list...
However, by definition, all items in a Python list between 0 and len(the_list)-1 exist (i.e., there is no need for a try, except if you know 0 <= index < len(the_list)).
You can use enumerate if you want the indexes between 0 and the last el...
Going from a framework to no-framework [closed]
...3rd-party ads/badges/videos. Already in WebKit. Likely to be at least partially implemented in Firefox 11.)
Content Security Policy (Firefox 4's new security framework, complimentary to the sandbox attribute. Now also being implemented in Chrome.)
If you're accepting HTML as input, I recommend gr...
In which order do CSS stylesheets override?
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Actually, !important participates directly in the cascade, and has nothing to do with specificity. Specificity is related to selectors, whereas !important is used with property declarations. (So you're right in saying that the ru...
Rails: How to reference images in CSS within Rails 4
... don't have the proper name adjusted. Here's what I mean. I have a file called logo.png. Yet when it shows up on heroku it is viewed as:
...
How to move a git repository into another directory and make that directory a git repository?
...create it)
$ cp -r gitrepo1 newrepo
# remove .git from old repo to delete all history and anything git from it
$ rm -rf gitrepo1/.git
Note that the copy is quite expensive if the repository is large and with a long history. You can avoid it easily too:
# move the directory instead
$ mv gitrepo1 ...
Why does std::getline() skip input after a formatted extraction?
..., it follows that it must be skipped or ignored somehow. One option is to call std::cin.ignore() after the the first extraction. It will discard the next available character so that the newline is no longer in the way.
std::getline(std::cin.ignore(), state)
In-Depth Explanation:
This is the overlo...
Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You should favor Select over ConvertAll as it works ...
Remove non-numeric characters (except periods and commas) from a string
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You could use preg_replace to swap out all non-numeric characters and the comma and period/full stop as follows:
$testString = '12.322,11T';
echo preg_replace('/[^0-9,.]+/', '', $testString);
The pattern can also be expressed as /[^\d,.]+/
...