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Is it possible to GROUP BY multiple columns using MySQL?
...garding SUM using with GROUP BY. If GROUP BY only by one column, then SUMs all values of each distinct (different) the column value sqlfiddle.com/#!9/1cbde2/2. If GROUP BY two columns. Then mysql at first checks if for the first column value there are different values in the second column. If yes, t...
pretty-print JSON using JavaScript
...or sure) and not HTML. Output can be seen inside console. You can edit the _variables inside the function adding some more styling.
function JSONstringify(json) {
if (typeof json != 'string') {
json = JSON.stringify(json, undefined, '\t');
}
var
arr = [],
_stri...
How To Change DataType of a DataColumn in a DataTable?
... of the column after the DataTable is filled, you can change it after you call FillSchema, but before you call Fill. For example, say the 3rd column is the one you want to convert from double to Int32, you could use:
adapter.FillSchema(table, SchemaType.Source);
table.Columns[2].DataType = typeof (...
getSupportActionBar from inside of Fragment ActionBarCompat
...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...
How does C compute sin() and other math functions?
...on in C, contributed by IBM. Since October 2011, this is the code that actually runs when you call sin() on a typical x86-64 Linux system. It is apparently faster than the fsin assembly instruction. Source code: sysdeps/ieee754/dbl-64/s_sin.c, look for __sin (double x).
This code is very complex. N...
Difference between assertEquals and assertSame in phpunit?
...
I use both sporadically, but according to the docs:
assertSame
Reports an error identified by $message if the two variables $expected and $actual do not have the same type and value."
And as you can see in the example below the above exc...
Uses of Action delegate in C# [closed]
... programming. (For more info on the computer science behind it read this: http://en.wikipedia.org/wiki/Map_(higher-order_function).
Now if you are using C# 3 you can slick this up a bit with a lambda expression like so:
using System;
using System.Collections.Generic;
class Program
{
static v...
How do I output coloured text to a Linux terminal?
...
You need to output ANSI colour codes. Note that not all terminals support this; if colour sequences are not supported, garbage will show up.
Example:
cout << "\033[1;31mbold red text\033[0m\n";
Here, \033 is the ESC character, ASCII 27. It is followed by [, then zero o...
Good ways to sort a queryset? - Django
...jango 1.4 and newer you can order by providing multiple fields.
Reference: https://docs.djangoproject.com/en/dev/ref/models/querysets/#order-by
order_by(*fields)
By default, results returned by a QuerySet are ordered by the ordering tuple given by the ordering option in the model’s Meta. You can...
Recommended date format for REST GET API
...dressability is not as important, you could also consider epoch time (e.g. http://example.com/start/1331162374). The URL looks a little cleaner, but you certainly lose readability.
The /2012/03/07 is another format you see a lot. You could expand upon that I suppose. If you go this route, just ma...