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What are the advantages of using a schema-free database like MongoDB compared to a relational databa
...ire several tables to properly represent in a relational db. This is especially useful if your data is immutable.
Deep query-ability. MongoDB supports dynamic queries on documents using a document-based query language that's nearly as powerful as SQL.
No schema migrations. Since MongoDB is schema-...
What are carriage return, linefeed, and form feed?
...as section separators. (It's uncommonly used in source code to divide logically independent functions or groups of functions.) Text editors can use this character when you "insert a page break". This is commonly escaped as \f, abbreviated FF, and has ASCII value 12 or 0x0C.
As control character...
How to search in array of object in mongodb
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Use $elemMatch to find the array of particular object
db.users.findOne({"_id": id},{awards: {$elemMatch: {award:'Turing Award', year:1977}}})
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How do I concatenate two strings in C?
...-terminator.
char* concat(const char *s1, const char *s2)
{
const size_t len1 = strlen(s1);
const size_t len2 = strlen(s2);
char *result = malloc(len1 + len2 + 1); // +1 for the null-terminator
// in real code you would check for errors in malloc here
memcpy(result, s1, len1);
...
Twitter image encoding challenge [closed]
... 4 = 64 colors) that simply gets blended in in some proportion. Mathematically, this is equivalent to a variable brightness and constant contrast adjustment for each color. Unfortunately, it also means there's no negative contrast to flip the colors.
Once it's computed the position, orientation a...
Naming “class” and “id” HTML attributes - dashes vs. underlines [closed]
...roblem and you could run into the same issue later where you would accidentally access an HTML Object instead of a JavaScript one
One remark, you can still access the HTML objects through the (for example) window object by using window['message-text'];
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How can I handle R CMD check “no visible binding for global variable” notes when my ggplot2 syntax i
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Just another warning. aes_string does not allow you to use functions to manipulate the x and y values. Say that you would like to log transform y in which case aes_string(x = 'x.values', y='log(y.values)') of course doesn't work. I use these kind of transformations a...
jquery disable form submit on enter
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Usually form is submitted on Enter when you have focus on input elements.
We can disable Enter key (code 13) on input elements within a form:
$('form input').on('keypress', function(e) {
return e.which !== 13;
});
DEMO: ...
Hide files with certain extension in Sublime Text Editor?
is it possible to hide all the files with certain extension from the sidebar (lateral nav bar) in Sublime Text Editor 3?
2 ...
How do you use Mongoose without defining a schema?
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Actually "Mixed" (Schema.Types.Mixed) mode appears to do exactly that in Mongoose...
it accepts a schema-less, freeform JS object - so whatever you can throw at it. It seems you have to trigger saves on that object manually afterwards, but it seems like a fair trad...