Tutorial by Examples: co

public enum Cassandra { DB; private Session session; private Cluster cluster; private static final Logger LOGGER = LoggerFactory.getLogger(Cassandra.class); /** * Connect to the cassandra database based on the connection configuration provided. * Multiple c...

In Vim, your configuration file is ~/.vimrc, with further configuration files in ~/.vim. In Neovim, configuration files are located in ~/.config/nvim. There is also no ~/.nvimrc file. Instead, use ~/.config/nvim/init.vim. You can import your Vim configuration directly into Neovim using this Unix c...

The only way if your components does not have a parent-child relationship (or are related but too further such as a grand grand grand son) is to have some kind of a signal that one component subscribes to, and the other writes into. Those are the 2 basic operations of any event system: subscribe/li...

If you have a stored DATE or DATETIME (in a column somewhere) it was stored with respect to some time zone, but in MySQL the time zone is not stored with the value. So, if you want to convert it to another time zone, you can, but you must know the original time zone. Using CONVERT_TZ() does the con...

SELECT NOW(3) does the trick.

CREATE TABLE times ( dt DATETIME(3), ts TIMESTAMP(3) ); makes a table with millisecond-precision date / time fields. INSERT INTO times VALUES (NOW(3), NOW(3)); inserts a row containing NOW() values with millisecond precision into the table. INSERT INTO times VALUES ('2015-01...

%f is the fractional precision format specifier for the DATE_FORMAT() function. SELECT DATE_FORMAT(NOW(3), '%Y-%m-%d %H:%i:%s.%f') displays a value like 2016-11-19 09:52:53.248000 with fractional microseconds. Because we used NOW(3), the final three digits in the fraction are 0.

If you have a Javascript timestamp value, for example 1478960868932, you can convert that to a MySQL fractional time value like this: FROM_UNIXTIME(1478960868932 * 0.001) It's simple to use that kind of expression to store your Javascript timestamp into a MySQL table. Do this: INSERT INTO table...

Here's an example of a React component with a "managed" input field. Whenever the value of the input field changes, an event handler is called which updates the state of the component with the new value of the input field. The call to setState in the event handler will trigger a call to ...

var gulp = require('gulp'); // include plug-ins var uglify = require('gulp-uglify'), concat = require('gulp-concat'); // Minified file gulp.task('packjsMin', function() { return gulp.src('node_modules/angular/*.js') .pipe(concat('script.js')) .pipe(uglify()) .p...

You can use docker, without using docker daemon (engine), by using cloud providers. In this example, you should have a gcloud (Google Cloud util), that connected to your account docker-machine create --driver google --google-project `your-project-name` google-machine-type f1-large fm02 This exa...

Given an m times n matrix A with n larger than m. The singular value decomposition [U,S,V] = svd(A); computes the matrices U,S,V. The matrix U consists of the left singular eigenvectors which are the eigenvectors of A*A.' while V consists of the right singular eigenvalues which are the eigenvec...

You might receive from your peer private key in PPK format, which seems it does not work in OpenSSH (command-line ssh). The client will be asking for the passphrase, because of OpenSSH bug. $ ssh -i mykey.ppk example.com Enter passphrase for mykey.ppk: You need to convert the key to OpenSSH for...

Visual Basic.NET, like most languages, permits recursion, a process by which a function calls itself under certain conditions. Here is a basic function in Visual Basic .NET to compute Fibonacci numbers. ''' <summary> ''' Gets the n'th Fibonacci number ''' </summary> ''' <param na...

request variables form url cgi

Server Application Session

variables this local arguments

This function shortens the text to a specified number of words and returns the shortened text. <?php echo wp_trim_words( get_the_content(), 40, '...' ); ?> In the above example we are passing the post content to the function. It will restrict the length of the content to 40 words and will ...

You can also use Laravel Artisan commands from your routes or controllers. To run a command using PHP code: Artisan::call('command-name'); For example, Artisan::call('db:seed');

Before using gcov, source code should be compiled with gcc using the two flags, -fprofile-arcs and -ftest-coverage. This tells the compiler to generate the information and extra object file code required by gcov. gcc -fprofile-arcs -ftest-coverage hello.c Linking should also use the -fprofile-a...