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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...

This fetches the value of NOW() in local time, in India Standard Time, and then again in UTC. SELECT NOW(); SET time_zone='Asia/Kolkata'; SELECT NOW(); SET time_zone='UTC'; SELECT NOW();

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...

Each server has a default global time_zone setting, configured by the owner of the server machine. You can find out the current time zone setting this way: SELECT @@time_zone Unfortunately, that usually yields the value SYSTEM, meaning the MySQL time is governed by the server OS's time zone sett...

To get a list of possible time_zone values in your MySQL server instance, use this command. SELECT mysql.time_zone_name.name Ordinarily, this shows the ZoneInfo list of time zones maintained by Paul Eggert at the Internet Assigned Numbers Authority. Worldwide there are appproximately 600 time z...

Javascript timestamps are based on the venerable UNIX time_t data type, and show the number of milliseconds since 1970-01-01 00:00:00 UTC. This expression gets the current time as a Javascript timestamp integer. (It does so correctly regardless of the current time_zone setting.) ROUND(UNIX_TIMEST...

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...

authenticate_with_http_token do |token, options| @user = User.find_by(auth_token: token) end You can test this endpoint with curl by making a request like curl -IH "Authorization: Token token=my-token" http://localhost:3000

RelativePanel has been introduced in Windows 10 and is used mainly to support adaptive layouts, where the child elements of the panel are laid out differently depending on available space. RelativePanel is typically used with visual states, which are used to switch the layout configuration, adaptin...

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 ...

We can use the get_bloginfo function to retrieve the email address of the site administrator. <?php echo get_bloginfo('admin_email'); ?>

For a non-main packages as well as main, instead of adding flags inside the code, write benchmarks in the test package , for example: func BenchmarkHello(b *testing.B) { for i := 0; i < b.N; i++ { fmt.Sprintf("hello") } } Then run the test with the profile flag ...

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...

grant all privileges on schema_name.* to 'new_user_name'@'%' identified by 'newpassword'; Attention: This can be used to create new root user

DROP TABLE Database.table_name

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...

Template Generic Syntax template<typename T> void f(ParamType param); f(expr); Case 1: ParamType is a Reference or Pointer, but not a Universal or Forward Reference. In this case type deduction works this way. The compiler ignores the reference part if it exists in expr. The compiler t...