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How do I query between two dates using MySQL?
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Personally, I find the term 'from' and 'to' a sneaky way to remember the order in which the query should be written.
– KeaganFouche
Jan 21 '19 at 22:04
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Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
...cross-use" %lf with float or %f with double.
But there's no reason to actually do it in practice. Don't use %f to printf arguments of type double. It is a widespread habit born back in C89/90 times, but it is a bad habit. Use %lf in printf for double and keep %f reserved for float arguments.
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CSS does the width include the padding?
...width: 10em; padding: 2em; border: 1em; }
would be 10em wide.
In contrast, all standards-fearing browsers default to the "content-box" box model. In this model, the width of an element does not include padding or borders. For example:
#foo { width: 10em; padding: 2em; border: 1em; }
will actually be...
How persistent is localStorage?
I'm depending heavily on localStorage for a plugin I'm writing. All the user settings are stored in it. Some settings require the user the write regex'es and they would be sad if their regex rules are gone at some point.
So now I am wondering just how persistent the localStorage is.
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How to store arrays in MySQL?
...raberry"
2 | "banana"
2 | "apple"
When you want to retrieve a person and all of their fruit you can do something like this:
SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name
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Why do C and C++ compilers allow array lengths in function signatures when they're never enforced?
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It is a quirk of the syntax for passing arrays to functions.
Actually it is not possible to pass an array in C. If you write syntax that looks like it should pass the array, what actually happens is that a pointer to the first element of the array is passed instead.
Since the pointer does...
Load and execute external js file in node.js with access to local variables?
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Just do a require('./yourfile.js');
Declare all the variables that you want outside access as global variables.
So instead of
var a = "hello" it will be
GLOBAL.a="hello" or just
a = "hello"
This is obviously bad. You don't want to be polluting the global scope.
Ins...
Core pool size vs maximum pool size in ThreadPoolExecutor
...When the queue is full new threads will be
created up to maxPoolSize. Once all the threads are in use and the
queue is full tasks will be rejected. As the queue reduces, so does
the number of active threads.
share
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How to search for file names in Visual Studio?
...e from Google or elsewhere, this answer is probably the best answer out of all of them.
To summarize, simply hit:
CTRL + ,
And then start typing the file name.
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improve this answer
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New to MongoDB Can not run command mongo
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After installing the MongoDB you should manually create a data folder.
By default MongoDB will store data in /data/db,
but it won't automatically create that directory. To create it, do:
$ sudo mkdir -p /data/db/
$ sudo chown `id -...