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SELECT DISTINCT ContinentCode FROM Countries; This query will return all DISTINCT (unique, different) values from ContinentCode column from Countries table ContinentCodeOCEUASNAAF SQLFiddle Demo

* on the word you want to substitute. :%s//replacement/g, leaving the find pattern empty.

Apart from the built-in colormaps defined in the colormaps reference (and their reversed maps, with '_r' appended to their name), custom colormaps can also be defined. The key is the matplotlib.cm module. The below example defines a very simple colormap using cm.register_cmap, containing a single c...

The original default colourmap of MATLAB (replaced in version R2014b) called jet is ubiquitous due to its high contrast and familiarity (and was the default of matplotlib for compatibility reasons). Despite its popularity, traditional colormaps often have deficiencies when it comes to representing d...

# config/locales/en.yml en: stackoverflow: header: title_html: "Use <strong>I18n</strong> with Tags & Symbols" Note the addition of extra _html after the name title. And in Views, # ERB <h2><%= t(:title_html, scope: [:stackoverflow, :heade...

We have a Product model and we want to group them by their category. Product.select(:category).group(:category) This will query the database as follows: SELECT "product"."category" FROM "product" GROUP BY "product"."category" Make sure that t...

If you want to remove duplicates from a result, you can use .distinct(): Customers.select(:country).distinct This queries the database as follows: SELECT DISTINCT "customers"."country" FROM "customers" .uniq() has the same effect. With Rails 5.0 it got deprecate...

The getopts builtin can be used inside functions to write functions that accommodate flags and optional parameters. This presents no special difficulty but one has to handle appropriately the values touched by getopts. As an example, we define a failwith function that writes a message on stderr an...

In elm, a function's value is computed when the last argument is applied. In the example below, the diagnostic from log will be printed when f is invoked with 3 arguments or a curried form of f is applied with the last argument. import String import Debug exposing (log) f a b c = String.join &...

Install the stable release from CRAN: install.packages("data.table") Or the development version from github: install.packages("data.table", type = "source", repos = "http://Rdatatable.github.io/data.table") To revert from devel to CRAN, the ...

This example will show how to get the mouse position relative to the canvas, such that (0,0) will be the top-left hand corner of the HTML5 Canvas. The e.clientX and e.clientY will get the mouse positions relative to the top of the document, to change this to be based on the top of the canvas we subt...

As the Clang front-end is designed for being compatible with GCC, most programs that can be compiled via GCC will compile when you swap g++ by clang++ in the build scripts. If no -std=version is given, gnu11 will be used. Windows users who are used to MSVC can swap cl.exe with clang-cl.exe. By defa...

BroadcastReceivers are used to receive broadcast Intents that are sent by the Android OS, other apps, or within the same app. Each Intent is created with an Intent Filter, which requires a String action. Additional information can be configured in the Intent. Likewise, BroadcastReceivers register ...

The symbol NA is for a logical missing value: class(NA) #[1] "logical" This is convenient, since it can easily be coerced to other atomic vector types, and is therefore usually the only NA you will need: x <- c(1, NA, 1) class(x[2]) #[1] "numeric" If you do need a s...

It is always recommend to go to the LLVM official website and follow the installation guides depending on your OS. If you are working on posix then in short you have to add one of the official LLVM package repositories. For example if you work on Ubuntu Xenial (16.04) you add a deb and deb-src entr...

There are currently three YouTube APIs available to the public: YouTube Data API YouTube Analytics API YouTube Reporting API Each of these offer different functionality and are treated as separate, individual APIs. Since YouTube is a subsidiary of Google, the various YouTube APIs are provid...

Macros are simple string replacements. (Strictly speaking, they work with preprocessing tokens, not arbitrary strings.) #include <stdio.h> #define SQUARE(x) x*x int main(void) { printf("%d\n", SQUARE(1+2)); return 0; } You may expect this code to print 9 (3*3), ...

DatePickerDialog is the simplest way to use DatePicker, because you can show dialog anywhere in your app. You don't have to implement your own layout with DatePicker widget. How to show dialog: DatePickerDialog datePickerDialog = new DatePickerDialog(context, listener, year, month, day); datePick...

Below are the PHP5 SuperGlobals $GLOBALS $_REQUEST $_GET $_POST $_FILES $_SERVER $_ENV $_COOKIE $_SESSION $GLOBALS: This SuperGlobal Variable is used for accessing globals variables. <?php $a = 10; function foo(){ echo $GLOBALS['a']; } //Which will print 10 Glo...

POST /token HTTP/1.1 Host: server.example.com Content-Type: application/x-www-form-urlencoded grant_type=password&username=[USERNAME]&password=[PASSWORD] &client_id=[APP_KEY]&client_secret=[APP_SECRET] Source