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NoSQL - MongoDB vs CouchDB [closed]
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If you are coming from the MySQL world, MongoDB is going to "feel" a lot more natural to you b...
Why is enum class preferred over plain enum?
...class Mammal { kangaroo, deer, human }; // another enum class
void fun() {
// examples of bad use of plain enums:
Color color = Color::red;
Card card = Card::green_card;
int num = color; // no problem
if (color == Card::red_card) // no problem (bad)
cout <...
Why did my Git repo enter a detached HEAD state?
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I reproduced this just now by accident:
lists the remote branches
git branch -r
origi...
Why doesn't String switch statement support a null case?
... Paul BelloraPaul Bellora
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How to format time since xxx e.g. “4 minutes ago” similar to Stack Exchange sites
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Might be an overkill in this case, but if the opportunity shows moment.js is just awesome!
Mo...
How to convert a data frame column to numeric type?
... you want to convert to numeric. I suggest that you should apply transform function in order to complete your task.
Now I'm about to demonstrate certain "conversion anomaly":
# create dummy data.frame
d <- data.frame(char = letters[1:5],
fake_char = as.character(1:5),
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How to efficiently build a tree from a flat structure?
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Store IDs of the objects in a hash table mapping to the specific object. Enumerate through all...
select * vs select column
... order; all his code broke as soon as someone else changed the table. What fun we had.
– Paul McKenzie
Jul 5 '10 at 15:06
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Compiler Ambiguous invocation error - anonymous method and method group with Func or Action
...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...
What is the difference between 'my' and 'our' in Perl?
...ariables. You can see that in the following program: package Foo; our $x = 123; package Bar; say $x;. If you want to "declare" a package variable, you need to use use vars qw( $x );. our $x; declares a lexically-scoped variable that is aliased to the same-named variable in the package in which the o...